diff --git a/assets/js/project_details.js b/assets/js/project_details.js
new file mode 100644
index 0000000..7925843
--- /dev/null
+++ b/assets/js/project_details.js
@@ -0,0 +1,295 @@
+document.addEventListener('DOMContentLoaded', () => {
+    const dataScript = document.getElementById('financial-data');
+    if (!dataScript) return;
+
+    const appData = JSON.parse(dataScript.textContent);
+    const { projectId, months, metrics, initialFinancialData, baseData, overrides } = appData;
+
+    let state = {
+        isOverrideActive: false,
+        overrideMonth: null,
+        originalTableState: {},
+        currentFinancialData: JSON.parse(JSON.stringify(initialFinancialData)) // Deep copy
+    };
+
+    const table = document.getElementById('financials-table');
+    if (!table) return;
+
+    // UTILITY FUNCTIONS
+    const formatCurrency = (value) => `€${(value || 0).toLocaleString('de-DE', { minimumFractionDigits: 2, maximumFractionDigits: 2 })}`;
+    const formatMargin = (value) => `${((value || 0) * 100).toFixed(2).replace('.', ',')}%`;
+    const parseLocaleNumber = (stringNumber) => {
+        if (typeof stringNumber !== 'string') return stringNumber;
+        // Remove thousands separators (.), then replace decimal comma with a period.
+        return Number(String(stringNumber).replace(/\./g, '').replace(',', '.'));
+    };
+
+    function debounce(func, wait) {
+        let timeout;
+        return function executedFunction(...args) {
+            const later = () => {
+                clearTimeout(timeout);
+                func(...args);
+            };
+            clearTimeout(timeout);
+            timeout = setTimeout(later, wait);
+        };
+    }
+
+
+    // MAIN LOGIC
+    function recalculateFinancials(overrideMonth, overrideValues) {
+        const newData = JSON.parse(JSON.stringify(state.currentFinancialData));
+        const overrideMonthIndex = months.indexOf(overrideMonth);
+
+        if (overrideMonthIndex === -1) {
+            console.error("Override month not found in months array!");
+            return state.currentFinancialData;
+        }
+
+        // Step 1: Apply the override values for the specific override month.
+        for (const key in overrideValues) {
+            overrideValues[key] = parseFloat(overrideValues[key] || 0);
+        }
+
+        newData['Opening Balance'][overrideMonth] = overrideValues['Opening Balance'];
+        newData.Billings[overrideMonth] = overrideValues.Billings;
+        newData.WIP[overrideMonth] = overrideValues.WIP;
+        newData.Expenses[overrideMonth] = overrideValues.Expenses;
+        newData.Cost[overrideMonth] = overrideValues.Cost;
+        newData.Payment[overrideMonth] = overrideValues.Payment;
+
+        let nsr = newData.WIP[overrideMonth] + newData.Billings[overrideMonth] - newData['Opening Balance'][overrideMonth] - newData.Expenses[overrideMonth];
+        newData.NSR[overrideMonth] = nsr;
+        let margin = (nsr !== 0) ? ((nsr - newData.Cost[overrideMonth]) / nsr) : 0;
+        newData.Margin[overrideMonth] = margin;
+        
+        // Step 2: Recalculate all subsequent months
+        for (let i = overrideMonthIndex + 1; i < months.length; i++) {
+            const month = months[i];
+            const prevMonth = months[i - 1];
+
+            const prevCumulativeBilling = parseFloat(newData.Billings[prevMonth] || 0);
+            const prevCumulativeCost = parseFloat(newData.Cost[prevMonth] || 0);
+            const prevCumulativeExpenses = parseFloat(newData.Expenses[prevMonth] || 0);
+            const prevWIP = parseFloat(newData.WIP[prevMonth] || 0);
+
+            const monthlyCost = parseFloat(baseData.monthly_costs[month] || 0);
+            const monthlyBilling = parseFloat(baseData.monthly_billing[month] || 0);
+            const monthlyExpenses = parseFloat(baseData.monthly_expenses[month] || 0);
+            const monthlyWIPChange = parseFloat(baseData.monthly_wip[month] || 0);
+
+            const newCumulativeBilling = prevCumulativeBilling + monthlyBilling;
+            const newCumulativeCost = prevCumulativeCost + monthlyCost;
+            const newCumulativeExpenses = prevCumulativeExpenses + monthlyExpenses;
+            const newWIP = prevWIP + monthlyExpenses + monthlyWIPChange - monthlyBilling;
+
+            newData.Billings[month] = newCumulativeBilling;
+            newData.Cost[month] = newCumulativeCost;
+            newData.Expenses[month] = newCumulativeExpenses;
+            newData.WIP[month] = newWIP;
+            
+            // THE FIX: Carry over the previous month's Net Service Revenue as the next month's Opening Balance.
+            newData['Opening Balance'][month] = newData.NSR[prevMonth] || 0;
+            newData.Payment[month] = 0;
+
+            nsr = newWIP + newCumulativeBilling - newData['Opening Balance'][month] - newCumulativeExpenses;
+            newData.NSR[month] = nsr;
+            margin = (nsr !== 0) ? ((nsr - newCumulativeCost) / nsr) : 0;
+            newData.Margin[month] = margin;
+        }
+
+        return newData;
+    }
+
+    function updateTable(newData) {
+        state.currentFinancialData = newData;
+        for (const metric of metrics) {
+            for (const month of months) {
+                const cell = table.querySelector(`td[data-month="${month}"][data-metric="${metric}"]`);
+                if (cell && cell.firstElementChild?.tagName !== 'INPUT') {
+                    const value = newData[metric][month];
+                    cell.textContent = metric === 'Margin' ? formatMargin(value) : formatCurrency(value);
+                }
+            }
+        }
+    }
+    
+    function recalculateForOverrideMonth(overrideMonth, overrideValues) {
+        const newData = JSON.parse(JSON.stringify(state.currentFinancialData)); // Deep copy
+
+        // Use the user's input values for the override month
+        newData['Opening Balance'][overrideMonth] = overrideValues['Opening Balance'];
+        newData.Billings[overrideMonth] = overrideValues.Billings;
+        newData.WIP[overrideMonth] = overrideValues.WIP;
+        newData.Expenses[overrideMonth] = overrideValues.Expenses;
+        newData.Cost[overrideMonth] = overrideValues.Cost;
+        newData.Payment[overrideMonth] = overrideValues.Payment;
+
+        // Recalculate dependent metrics for the override month
+        const nsr = newData.WIP[overrideMonth] + newData.Billings[overrideMonth] - newData['Opening Balance'][overrideMonth] - newData.Expenses[overrideMonth];
+        newData.NSR[overrideMonth] = nsr;
+        const margin = (nsr !== 0) ? ((nsr - newData.Cost[overrideMonth]) / nsr) : 0;
+        newData.Margin[overrideMonth] = margin;
+
+        return newData;
+    }
+
+    function handleInputChange() {
+        const overrideValues = {};
+        const editableMetrics = ['Opening Balance', 'Billings', 'WIP', 'Expenses', 'Cost', 'Payment'];
+        editableMetrics.forEach(metric => {
+            const input = table.querySelector(`td[data-month="${state.overrideMonth}"][data-metric="${metric}"] input`);
+            overrideValues[metric] = parseLocaleNumber(input.value) || 0;
+        });
+
+        const recalculatedData = recalculateForOverrideMonth(state.overrideMonth, overrideValues);
+        updateTable(recalculatedData);
+    }
+
+    function enterOverrideMode(month) {
+        if (state.isOverrideActive) return;
+        
+        state.isOverrideActive = true;
+        state.overrideMonth = month;
+
+        const editableMetrics = ['Opening Balance', 'Billings', 'WIP', 'Expenses', 'Cost', 'Payment'];
+
+        metrics.forEach(metric => {
+            const cell = table.querySelector(`td[data-month="${month}"][data-metric="${metric}"]`);
+            if (!cell) return;
+
+            const originalValue = state.currentFinancialData[metric][month];
+            state.originalTableState[metric] = cell.innerHTML;
+
+            if (editableMetrics.includes(metric)) {
+                // Ensure originalValue is a number before formatting
+                const numericValue = (typeof originalValue === 'number') ? originalValue : 0;
+                // Format to locale string with comma decimal separator for the input value
+                const localeValue = numericValue.toLocaleString('de-DE', { minimumFractionDigits: 2, maximumFractionDigits: 2 });
+                cell.innerHTML = `<input type="text" class="form-control form-control-sm" value="${localeValue}">`;
+            }
+        });
+        
+        const debouncedRecalc = debounce(handleInputChange, 200);
+        table.querySelectorAll(`td[data-month="${month}"] input`).forEach(input => {
+            input.addEventListener('input', debouncedRecalc);
+        });
+
+        const buttonCell = table.querySelector(`th button[data-month="${month}"]`).parentElement;
+        state.originalTableState['button'] = buttonCell.innerHTML;
+        buttonCell.innerHTML = `
+            <div class="btn-group btn-group-sm mt-1" role="group">
+                <button type="button" class="btn btn-success confirm-override">Confirm</button>
+                <button type="button" class="btn btn-danger cancel-override">Cancel</button>
+            </div>
+        `;
+    }
+    
+    async function confirmOverride() {
+        try {
+            const overrideValues = {};
+            const editableMetrics = ['Opening Balance', 'Billings', 'WIP', 'Expenses', 'Cost', 'Payment'];
+            editableMetrics.forEach(metric => {
+                const input = table.querySelector(`td[data-month="${state.overrideMonth}"][data-metric="${metric}"] input`);
+                if (!input) {
+                    throw new Error(`Could not find input for metric: ${metric} in month ${state.overrideMonth}`);
+                }
+                overrideValues[metric] = parseLocaleNumber(input.value) || 0;
+            });
+
+            const finalData = recalculateFinancials(state.overrideMonth, overrideValues);
+
+            const monthsToSave = months.slice(months.indexOf(state.overrideMonth));
+            const dataToSave = {};
+            monthsToSave.forEach(month => {
+                dataToSave[month] = {};
+                metrics.forEach(metric => {
+                    const rawValue = finalData[metric][month];
+                    let cleanValue = typeof rawValue === 'string' ? parseLocaleNumber(rawValue) : rawValue;
+
+                    if (!isFinite(cleanValue)) {
+                        console.warn(`Invalid number for ${metric} in ${month}. Resetting to 0. Original:`, rawValue);
+                        cleanValue = 0;
+                    }
+                    dataToSave[month][metric] = cleanValue;
+                });
+            });
+
+            const payload = {
+                project_id: projectId,
+                overrides: Object.entries(dataToSave).map(([month, values]) => ({
+                    month: month,
+                    opening_balance: values['Opening Balance'],
+                    payment: values.Payment,
+                    wip: values.WIP,
+                    expenses: values.Expenses,
+                    cost: values.Cost,
+                    nsr: values.NSR,
+                    margin: values.Margin,
+                    is_confirmed: month === state.overrideMonth ? 1 : 0
+                }))
+            };
+
+            
+
+            const response = await fetch('save_override.php?t=' + new Date().getTime(), {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                },
+                body: JSON.stringify(payload)
+            });
+
+            if (!response.ok) {
+                let errorMsg = `HTTP error! status: ${response.status}`;
+                try {
+                    const errorData = await response.json();
+                    errorMsg = errorData.message || errorMsg;
+                } catch (e) {
+                    // Not a JSON response
+                }
+                throw new Error(errorMsg);
+            }
+
+            const result = await response.json();
+            if (result.success) {
+                alert(result.message || 'Override confirmed successfully!');
+                window.location.reload();
+            } else {
+                throw new Error(result.message || 'Failed to save override.');
+            }
+        } catch (error) {
+            console.error('Error confirming override:', error);
+            alert(`Error: ${error.message}`);
+        }
+    }
+
+    function exitOverrideMode() {
+        metrics.forEach(metric => {
+            const cell = table.querySelector(`td[data-month="${state.overrideMonth}"][data-metric="${metric}"]`);
+            if (cell) {
+                cell.innerHTML = state.originalTableState[metric];
+            }
+        });
+        
+        const buttonCell = table.querySelector(`th .btn-group`).parentElement;
+        buttonCell.innerHTML = state.originalTableState['button'];
+
+        updateTable(initialFinancialData);
+
+        state.isOverrideActive = false;
+        state.overrideMonth = null;
+        state.originalTableState = {};
+    }
+
+    table.addEventListener('click', (e) => {
+        if (e.target.classList.contains('override-btn')) {
+            enterOverrideMode(e.target.dataset.month);
+        } else if (e.target.classList.contains('confirm-override')) {
+            confirmOverride();
+        } else if (e.target.classList.contains('cancel-override')) {
+            exitOverrideMode();
+        }
+    });
+});
\ No newline at end of file
diff --git a/db/migrate.php b/db/migrate.php
new file mode 100644
index 0000000..b3df702
--- /dev/null
+++ b/db/migrate.php
@@ -0,0 +1,81 @@
+<?php
+// Simple migration script
+require_once __DIR__ . '/config.php';
+
+try {
+    $pdo = db();
+    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+    // Create migrations table if it doesn't exist
+    $pdo->exec("CREATE TABLE IF NOT EXISTS migrations (
+        id INT AUTO_INCREMENT PRIMARY KEY,
+        migration_name VARCHAR(255) NOT NULL,
+        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+    )");
+
+    // Get all migration files
+    $migrationFiles = glob(__DIR__ . '/migrations/*.sql');
+    
+    // Get already run migrations
+    $stmt = $pdo->query("SELECT migration_name FROM migrations");
+    $runMigrations = $stmt->fetchAll(PDO::FETCH_COLUMN);
+
+    echo '<html><head><title>Database Migrations</title>';
+    echo '<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">';
+    echo '<style>body { padding: 2rem; } .log { font-family: monospace; white-space: pre; } </style>';
+    echo '</head><body><div class="container">';
+    echo '<h1>Database Migrations</h1>';
+
+    $migrationsApplied = false;
+
+    foreach ($migrationFiles as $file) {
+        $migrationName = basename($file);
+        if (!in_array($migrationName, $runMigrations)) {
+            echo '<div class="alert alert-info log">Applying migration: ' . htmlspecialchars($migrationName) . '...</div>';
+            $sql = file_get_contents($file);
+            $statements = array_filter(array_map('trim', explode(';', $sql)));
+            $fileHasError = false;
+
+            foreach ($statements as $statement) {
+                if (empty($statement)) continue;
+                try {
+                    $pdo->exec($statement);
+                } catch (PDOException $e) {
+                    // 1060 is the specific error code for "Duplicate column name"
+                    if (strpos($e->getMessage(), '1060') !== false) {
+                        // It's a duplicate column error, we can ignore it.
+                        echo '<div class="alert alert-warning log">Ignoring existing column in ' . htmlspecialchars($migrationName) . '.</div>';
+                    } else {
+                        // It's another error, so we should stop.
+                        echo '<div class="alert alert-danger log">Error applying migration ' . htmlspecialchars($migrationName) . ': ' . htmlspecialchars($e->getMessage()) . '</div>';
+                        $fileHasError = true;
+                        break; // break from statements loop
+                    }
+                }
+            }
+
+            if (!$fileHasError) {
+                // Record migration
+                $stmt = $pdo->prepare("INSERT INTO migrations (migration_name) VALUES (?)");
+                $stmt->execute([$migrationName]);
+                
+                echo '<div class="alert alert-success log">Successfully applied ' . htmlspecialchars($migrationName) . '</div>';
+                $migrationsApplied = true;
+            } else {
+                // Stop on error
+                break; // break from files loop
+            }
+        }
+    }
+
+    if (!$migrationsApplied) {
+        echo '<div class="alert alert-success log">Database is already up to date.</div>';
+    }
+
+    echo '<a href="/" class="btn btn-primary mt-3">Back to Home</a>';
+    echo '</div></body></html>';
+
+} catch (PDOException $e) {
+    http_response_code(500);
+    die("Database connection failed: " . $e->getMessage());
+}
\ No newline at end of file
diff --git a/db/migrations/005_create_project_finance_monthly_table.sql b/db/migrations/005_create_project_finance_monthly_table.sql
index e0d9ee7..e8d9d00 100644
--- a/db/migrations/005_create_project_finance_monthly_table.sql
+++ b/db/migrations/005_create_project_finance_monthly_table.sql
@@ -1,11 +1,19 @@
+DROP TABLE IF EXISTS `projectFinanceMonthly`;
+
 CREATE TABLE IF NOT EXISTS `projectFinanceMonthly` (
     `id` INT AUTO_INCREMENT PRIMARY KEY,
     `projectId` INT NOT NULL,
-    `metricName` VARCHAR(255) NOT NULL,
     `month` DATE NOT NULL,
-    `amount` DECIMAL(15, 2) NOT NULL,
+    `opening_balance` DECIMAL(15, 2) DEFAULT 0,
+    `payment` DECIMAL(15, 2) DEFAULT 0,
+    `wip` DECIMAL(15, 2) DEFAULT 0,
+    `expenses` DECIMAL(15, 2) DEFAULT 0,
+    `cost` DECIMAL(15, 2) DEFAULT 0,
+    `nsr` DECIMAL(15, 2) DEFAULT 0,
+    `margin` DECIMAL(15, 5) DEFAULT 0,
+    `is_confirmed` TINYINT(1) NOT NULL DEFAULT 0,
     `createdAt` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     `updatedAt` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
     FOREIGN KEY (`projectId`) REFERENCES `projects`(`id`) ON DELETE CASCADE,
-    UNIQUE KEY `project_metric_month` (`projectId`, `metricName`, `month`)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+    UNIQUE KEY `unique_project_month` (`projectId`, `month`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
\ No newline at end of file
diff --git a/db/migrations/007_add_revenue_fields_to_roster.sql b/db/migrations/007_add_revenue_fields_to_roster.sql
index 8590309..0143998 100644
--- a/db/migrations/007_add_revenue_fields_to_roster.sql
+++ b/db/migrations/007_add_revenue_fields_to_roster.sql
@@ -1,3 +1,2 @@
-ALTER TABLE `roster`
-ADD COLUMN `grossRevenue` DECIMAL(10, 2) NOT NULL DEFAULT 0.00,
-ADD COLUMN `discountedRevenue` DECIMAL(10, 2) NOT NULL DEFAULT 0.00;
+ALTER TABLE `roster` ADD COLUMN `grossRevenue` DECIMAL(10, 2) NOT NULL DEFAULT 0.00;
+ALTER TABLE `roster` ADD COLUMN `discountedRevenue` DECIMAL(10, 2) NOT NULL DEFAULT 0.00;
diff --git a/db/migrations/009_create_project_finance_monthly_override_table.sql b/db/migrations/009_create_project_finance_monthly_override_table.sql
new file mode 100644
index 0000000..fdf98b6
--- /dev/null
+++ b/db/migrations/009_create_project_finance_monthly_override_table.sql
@@ -0,0 +1,10 @@
+CREATE TABLE IF NOT EXISTS `project_finance_monthly_override` (
+    `project_id` INT NOT NULL,
+    `nsr_override` DECIMAL(15, 2) DEFAULT NULL,
+    `cost_override` DECIMAL(15, 2) DEFAULT NULL,
+    `hours_override` DECIMAL(10, 2) DEFAULT NULL,
+    `createdAt` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    `updatedAt` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    PRIMARY KEY (`project_id`),
+    FOREIGN KEY (`project_id`) REFERENCES `projects`(`id`) ON DELETE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
\ No newline at end of file
diff --git a/db/migrations/010_alter_override_table.sql b/db/migrations/010_alter_override_table.sql
new file mode 100644
index 0000000..5159dc3
--- /dev/null
+++ b/db/migrations/010_alter_override_table.sql
@@ -0,0 +1,14 @@
+-- Step 1: Drop the foreign key constraint
+ALTER TABLE project_finance_monthly_override DROP FOREIGN KEY project_finance_monthly_override_ibfk_1;
+
+-- Step 2: Drop the old primary key
+ALTER TABLE project_finance_monthly_override DROP PRIMARY KEY;
+
+-- Step 3: Add the new month column
+ALTER TABLE project_finance_monthly_override ADD COLUMN month VARCHAR(7) NOT NULL;
+
+-- Step 4: Add the new composite primary key
+ALTER TABLE project_finance_monthly_override ADD PRIMARY KEY (project_id, month);
+
+-- Step 5: Re-add the foreign key constraint with a more descriptive name
+ALTER TABLE project_finance_monthly_override ADD CONSTRAINT fk_override_project_id FOREIGN KEY (project_id) REFERENCES projects(id) ON DELETE CASCADE;
diff --git a/describe_table.php b/describe_table.php
new file mode 100644
index 0000000..2fd72e0
--- /dev/null
+++ b/describe_table.php
@@ -0,0 +1,12 @@
+<?php
+require_once 'db/config.php';
+
+try {
+    $pdo = db();
+    $stmt = $pdo->query("DESCRIBE project_finance_monthly_override");
+    $columns = $stmt->fetchAll(PDO::FETCH_ASSOC);
+    print_r($columns);
+} catch (Exception $e) {
+    echo "Error: " . $e->getMessage();
+}
+?>
\ No newline at end of file
diff --git a/logs/php_errors.log b/logs/php_errors.log
new file mode 100644
index 0000000..6fc7ef1
--- /dev/null
+++ b/logs/php_errors.log
@@ -0,0 +1,20 @@
+[26-Nov-2025 13:29:03 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:03 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:08 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:08 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:13 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:13 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:19 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:19 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:24 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:24 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:29 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:29 UTC] save_override.php: Invalid request method
+[26-Nov-2025 13:29:29 UTC] save_override.php: Script start
+[26-Nov-2025 13:29:29 UTC] save_override.php: JSON data decoded
+[26-Nov-2025 13:29:29 UTC] save_override.php: Database connection successful
+[26-Nov-2025 13:29:29 UTC] save_override.php: Starting database transaction
+[26-Nov-2025 13:29:29 UTC] save_override.php: SQL statement prepared
+[26-Nov-2025 13:29:29 UTC] save_override.php: Processing month: 2025-11-01
+[26-Nov-2025 13:29:29 UTC] save_override.php: An exception occurred: SQLSTATE[22001]: String data, right truncated: 1406 Data too long for column 'month' at row 1
+[26-Nov-2025 13:29:29 UTC] save_override.php: Rolling back transaction
diff --git a/logs/raw_input.log b/logs/raw_input.log
new file mode 100644
index 0000000..00786fd
--- /dev/null
+++ b/logs/raw_input.log
@@ -0,0 +1,24 @@
+{"project_id":25,"overrides":[{"month":"2025-11-01","nsr":27855,"cost":1350},{"month":"2025-12-01","nsr":35545,"cost":2600},{"month":"2026-01-01","nsr":43355,"cost":3225}]}Executing with params: Array
+(
+    [:project_id] => 25
+    [:month] => 2025-11-01
+    [:nsr_override] => 27855
+    [:cost_override] => 1350
+    [:hours_override] => 
+)
+Executing with params: Array
+(
+    [:project_id] => 25
+    [:month] => 2025-12-01
+    [:nsr_override] => 35545
+    [:cost_override] => 2600
+    [:hours_override] => 
+)
+Executing with params: Array
+(
+    [:project_id] => 25
+    [:month] => 2026-01-01
+    [:nsr_override] => 43355
+    [:cost_override] => 3225
+    [:hours_override] => 
+)
diff --git a/project_details.php b/project_details.php
index 08fc482..eb9463f 100644
--- a/project_details.php
+++ b/project_details.php
@@ -10,7 +10,7 @@ function execute_sql_from_file($pdo, $filepath) {
         return true;
     } catch (PDOException $e) {
         // Ignore errors about tables/columns that already exist
-        if (strpos($e->getMessage(), 'already exists') === false && strpos($e->getMessage(), 'Duplicate column name') === false) {
+        if (strpos($e->getMessage(), 'already exists') === false && strpos($e->getMessage(), 'Duplicate column name') === false && strpos($e->getMessage(), 'Duplicate key name') === false) {
             error_log("SQL Execution Error in $filepath: " . $e->getMessage());
         }
         return false;
@@ -35,7 +35,7 @@ $project = null;
 $project_id = $_GET['id'] ?? null;
 $financial_data = [];
 $months = [];
-$metrics = ["Opening Balance", "Billings", "WIP", "Expenses", "Cost", "NSR", "Margin"];
+$metrics = ["Opening Balance", "Billings", "WIP", "Expenses", "Cost", "NSR", "Margin", "Payment"];
 
 if ($project_id) {
     $stmt = $pdo->prepare("SELECT * FROM projects WHERE id = :id");
@@ -103,6 +103,15 @@ if ($project_id) {
         $expenses_stmt->execute([':pid' => $project_id]);
         $monthly_expenses = $expenses_stmt->fetchAll(PDO::FETCH_KEY_PAIR);
 
+        // Fetch confirmed override data
+        $finance_override_stmt = $pdo->prepare("SELECT * FROM projectFinanceMonthly WHERE projectId = :pid ORDER BY month ASC");
+        $finance_override_stmt->execute([':pid' => $project_id]);
+        $overrides_raw = $finance_override_stmt->fetchAll(PDO::FETCH_ASSOC);
+        $finance_overrides = [];
+        foreach ($overrides_raw as $row) {
+            $finance_overrides[$row['month']] = $row;
+        }
+
         // 2. Calculate cumulative values month by month
         $cumulative_billing = 0;
         $cumulative_cost = 0;
@@ -110,36 +119,54 @@ if ($project_id) {
         $previous_month_wip = 0;
 
         foreach ($months as $month) {
-            // Normalize month keys from fetched data
-            $cost = $monthly_costs[$month] ?? 0;
-            $base_monthly_wip = $monthly_wip[$month] ?? 0;
-            $billing = $monthly_billing[$month] ?? 0;
-            $expenses = $monthly_expenses[$month] ?? 0;
+            if (isset($finance_overrides[$month])) {
+                // This month has saved data. Use its values.
+                $financial_data['Opening Balance'][$month] = $finance_overrides[$month]['opening_balance'];
+                $financial_data['Billings'][$month]      = $finance_overrides[$month]['payment'];
+                $financial_data['Payment'][$month]       = $finance_overrides[$month]['payment'];
+                $financial_data['WIP'][$month]           = $finance_overrides[$month]['wip'];
+                $financial_data['Expenses'][$month]      = $finance_overrides[$month]['expenses'];
+                $financial_data['Cost'][$month]          = $finance_overrides[$month]['cost'];
+                $financial_data['NSR'][$month]           = $finance_overrides[$month]['nsr'];
+                $financial_data['Margin'][$month]        = $finance_overrides[$month]['margin'];
 
-            // Cumulative calculations
-            $cumulative_billing += $billing;
-            $cumulative_cost += $cost;
-            $cumulative_expenses += $expenses;
+                // Update cumulative trackers for the next potential calculation
+                $cumulative_billing = $financial_data['Billings'][$month];
+                $cumulative_cost    = $financial_data['Cost'][$month];
+                $cumulative_expenses= $financial_data['Expenses'][$month];
+                $previous_month_wip = $financial_data['WIP'][$month];
+            } else {
+                // This month has no saved data. Calculate as usual.
+                $cost = $monthly_costs[$month] ?? 0;
+                $base_monthly_wip = $monthly_wip[$month] ?? 0;
+                $billing = $monthly_billing[$month] ?? 0;
+                $expenses = $monthly_expenses[$month] ?? 0;
 
-            // WIP Calculation (new formula)
-            // current month WIP = previous month WIP + Month Expenses + base_monthly_wip - month Billing
-            $current_wip = $previous_month_wip + $expenses + $base_monthly_wip - $billing;
+                // Cumulative calculations
+                $cumulative_billing += $billing;
+                $cumulative_cost += $cost;
+                $cumulative_expenses += $expenses;
 
-            $financial_data['WIP'][$month] = $current_wip;
-            $financial_data['Billings'][$month] = $cumulative_billing;
-            $financial_data['Cost'][$month] = $cumulative_cost;
-            $financial_data['Opening Balance'][$month] = 0; // Placeholder
-            $financial_data['Expenses'][$month] = $cumulative_expenses;
+                // WIP Calculation
+                $current_wip = $previous_month_wip + $expenses + $base_monthly_wip - $billing;
 
-            // Calculated metrics (NSR and Margin)
-            $nsr = $financial_data['WIP'][$month] + $financial_data['Billings'][$month] - $financial_data['Opening Balance'][$month] - $financial_data['Expenses'][$month];
-            $financial_data['NSR'][$month] = $nsr;
+                $financial_data['WIP'][$month] = $current_wip;
+                $financial_data['Billings'][$month] = $cumulative_billing;
+                $financial_data['Cost'][$month] = $cumulative_cost;
+                $financial_data['Opening Balance'][$month] = 0; // Placeholder
+                $financial_data['Expenses'][$month] = $cumulative_expenses;
+                $financial_data['Payment'][$month] = 0; // Not overridden, so no payment input
 
-            $margin = ($nsr != 0) ? (($nsr - $financial_data['Cost'][$month]) / $nsr) : 0;
-            $financial_data['Margin'][$month] = $margin;
+                // Calculated metrics (NSR and Margin)
+                $nsr = $financial_data['WIP'][$month] + $financial_data['Billings'][$month] - $financial_data['Opening Balance'][$month] - $financial_data['Expenses'][$month];
+                $financial_data['NSR'][$month] = $nsr;
 
-            // Update previous month's WIP for the next iteration
-            $previous_month_wip = $current_wip;
+                $margin = ($nsr != 0) ? (($nsr - $financial_data['Cost'][$month]) / $nsr) : 0;
+                $financial_data['Margin'][$month] = $margin;
+
+                // Update previous month's WIP for the next iteration
+                $previous_month_wip = $current_wip;
+            }
         }
     }
 }
@@ -232,21 +259,45 @@ if (!$project) {
                         </div>
                     </div>
                     <div class="table-responsive">
-                        <table class="table table-bordered table-hover">
+                        <?php
+                        // Determine override eligibility
+                        $override_eligible_month = null;
+                        foreach ($months as $month) {
+                            if (!isset($finance_overrides[$month]) || !$finance_overrides[$month]['is_confirmed']) {
+                                $override_eligible_month = $month;
+                                break;
+                            }
+                        }
+                        ?>
+                        <table class="table table-bordered table-hover" id="financials-table">
                             <thead>
                                 <tr class="text-center">
                                     <th class="bg-body-tertiary" style="min-width: 150px;">Metric</th>
                                     <?php foreach ($months as $month): ?>
-                                        <th><?php echo date('M Y', strtotime($month)); ?></th>
+                                        <th>
+                                            <?php echo date('M Y', strtotime($month)); ?><br>
+                                            <?php
+                                                $is_confirmed = isset($finance_overrides[$month]) && $finance_overrides[$month]['is_confirmed'];
+                                                $is_eligible = ($month === $override_eligible_month);
+
+                                                if ($is_confirmed) {
+                                                    echo '<span class="badge bg-success mt-1">Confirmed</span>';
+                                                } elseif ($is_eligible) {
+                                                    echo '<button class="btn btn-sm btn-warning override-btn mt-1" data-month="' . $month . '">Override</button>';
+                                                } else {
+                                                    echo '<button class="btn btn-sm btn-secondary mt-1" disabled>Override</button>';
+                                                }
+                                            ?>
+                                        </th>
                                     <?php endforeach; ?>
                                 </tr>
                             </thead>
                             <tbody>
                                 <?php foreach ($metrics as $metric): ?>
-                                <tr>
+                                <tr data-metric="<?php echo htmlspecialchars($metric); ?>">
                                     <td class="fw-bold bg-body-tertiary"><?php echo $metric; ?></td>
                                     <?php foreach ($months as $month): ?>
-                                        <td class="text-end">
+                                        <td class="text-end financial-metric" data-month="<?php echo $month; ?>" data-metric="<?php echo htmlspecialchars($metric); ?>">
                                             <?php 
                                                 if ($metric === 'Margin') {
                                                     echo number_format(($financial_data[$metric][$month] ?? 0) * 100, 2) . '%';
@@ -267,6 +318,42 @@ if (!$project) {
         </main>
     </div>
 
+<script id="financial-data" type="application/json">
+<?php
+    $project_id_js = $project['id'];
+    
+    $finance_overrides_js = [];
+    foreach($finance_overrides as $month => $data) {
+        $finance_overrides_js[$month] = [
+            'is_confirmed' => $data['is_confirmed'],
+            'Opening Balance' => $data['opening_balance'],
+            'Billings' => $data['payment'],
+            'Payment' => $data['payment'],
+            'WIP' => $data['wip'],
+            'Expenses' => $data['expenses'],
+            'Cost' => $data['cost'],
+            'NSR' => $data['nsr'],
+            'Margin' => $data['margin']
+        ];
+    }
+
+    $js_data = [
+        'projectId' => $project_id_js,
+        'months' => $months,
+        'metrics' => $metrics,
+        'initialFinancialData' => $financial_data,
+        'baseData' => [
+            'monthly_costs' => $monthly_costs,
+            'monthly_wip' => $monthly_wip,
+            'monthly_billing' => $monthly_billing,
+            'monthly_expenses' => $monthly_expenses,
+        ],
+        'overrides' => $finance_overrides_js
+    ];
+    echo json_encode($js_data, JSON_PRETTY_PRINT);
+?>
+</script>
 <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js"></script>
+<script src="assets/js/project_details.js?v=<?php echo time(); ?>"></script>
 </body>
 </html>
\ No newline at end of file
diff --git a/save_override.php b/save_override.php
new file mode 100644
index 0000000..678ee7f
--- /dev/null
+++ b/save_override.php
@@ -0,0 +1,93 @@
+<?php
+require_once 'db/config.php';
+
+header('Content-Type: application/json');
+
+$raw_input = file_get_contents('php://input');
+$response = ['success' => false, 'message' => 'An error occurred.'];
+$pdo = null;
+
+try {
+    $pdo = db();
+    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+    $data = json_decode($raw_input, true);
+
+    if (empty($data['project_id']) || empty($data['overrides'])) {
+        throw new Exception("Project ID or overrides data not provided.");
+    }
+
+    $project_id = $data['project_id'];
+    $overrides = $data['overrides'];
+    $rows_affected_total = 0;
+
+    $pdo->beginTransaction();
+
+    $sql = "
+        INSERT INTO projectFinanceMonthly (projectId, month, opening_balance, payment, wip, expenses, cost, nsr, margin, is_confirmed)
+        VALUES (:project_id, :month, :opening_balance, :payment, :wip, :expenses, :cost, :nsr, :margin, :is_confirmed)
+        ON DUPLICATE KEY UPDATE
+            opening_balance = VALUES(opening_balance),
+            payment = VALUES(payment),
+            wip = VALUES(wip),
+            expenses = VALUES(expenses),
+            cost = VALUES(cost),
+            nsr = VALUES(nsr),
+            margin = VALUES(margin),
+            is_confirmed = VALUES(is_confirmed)
+    ";
+    $stmt = $pdo->prepare($sql);
+
+    foreach ($overrides as $override) {
+        $date = new DateTime($override['month']);
+        $month = $date->format('Y-m-d');
+
+        $params = [
+            ':project_id' => $project_id,
+            ':month' => $month,
+            ':opening_balance' => $override['opening_balance'] ?? null,
+            ':payment' => $override['payment'] ?? null,
+            ':wip' => $override['wip'] ?? null,
+            ':expenses' => $override['expenses'] ?? null,
+            ':cost' => $override['cost'] ?? null,
+            ':nsr' => $override['nsr'] ?? null,
+            ':margin' => $override['margin'] ?? null,
+            ':is_confirmed' => $override['is_confirmed'] ?? 0,
+        ];
+        $stmt->execute($params);
+        $rows_affected_total += $stmt->rowCount();
+    }
+
+    if ($rows_affected_total === 0) {
+        // It's possible that the data is identical, so 0 affected rows is not strictly an error.
+        // We can consider it a "soft" success.
+        $pdo->rollBack(); // Rollback to not leave an open transaction
+        $response['success'] = true; // Report success to the frontend
+        $response['message'] = 'No changes were detected. Nothing was saved.';
+        echo json_encode($response);
+        exit;
+    }
+
+    $pdo->commit();
+
+    $response['success'] = true;
+    $response['message'] = 'Override data saved successfully. ' . $rows_affected_total . ' records were updated.';
+
+} catch (PDOException $e) {
+    if ($pdo && $pdo->inTransaction()) {
+        $pdo->rollBack();
+    }
+    error_log("save_override.php: PDOException caught: " . $e->getMessage());
+    $response['message'] = "Database Error: " . $e->getMessage();
+    http_response_code(500);
+} catch (Exception $e) {
+    if ($pdo && $pdo->inTransaction()) {
+        $pdo->rollBack();
+    }
+    error_log("save_override.php: Exception caught: " . $e->getMessage());
+    $response['message'] = "General Error: " . $e->getMessage();
+    http_response_code(500);
+}
+
+echo json_encode($response);
+?>
\ No newline at end of file
diff --git a/test_save.php b/test_save.php
new file mode 100644
index 0000000..92024ea
--- /dev/null
+++ b/test_save.php
@@ -0,0 +1,27 @@
+<?php
+$url = 'http://localhost/save_override.php';
+$data = [
+    'project_id' => 25,
+    'overrides' => [
+        ['month' => '2025-11-01', 'nsr' => 1000, 'cost' => 500],
+        ['month' => '2025-12-01', 'nsr' => 2000, 'cost' => 1000],
+    ]
+];
+
+$options = [
+    'http' => [
+        'header'  => "Content-type: application/json\r\n",
+        'method'  => 'POST',
+        'content' => json_encode($data),
+    ],
+];
+
+$context  = stream_context_create($options);
+$result = file_get_contents($url, false, $context);
+
+if ($result === FALSE) { 
+    echo "Error fetching URL";
+}
+
+var_dump($result);
+?>
diff --git a/test_sql.php b/test_sql.php
new file mode 100644
index 0000000..53670ad
--- /dev/null
+++ b/test_sql.php
@@ -0,0 +1,12 @@
+<?php
+require_once 'db/config.php';
+
+try {
+    $pdo = db();
+    $sql = "INSERT INTO project_finance_monthly_override (project_id, month, nsr_override, cost_override) VALUES (25, '2025-11-01', 1000, 500)";
+    $pdo->exec($sql);
+    echo "Insert successful.";
+} catch (Exception $e) {
+    echo "Error: " . $e->getMessage();
+}
+?>
\ No newline at end of file