# Phase 10.9.1 — Revenue Parity QA JSON Integrity Hotfix

## Root cause

The Phase 10.9 live Revenue parity calculation itself executed successfully and produced 10/10 PASS results with zero differences.

The failure was limited to the QA endpoint:

- `public/phase10-9-revenue-parity-qa.php`
- A double-quoted source-marker string interpolated `$to->format('Y')`.
- PHP emitted a Notice before the JSON body.
- PowerShell `ConvertFrom-Json` rejected the contaminated response.

## Fix

1. Escape the PHP variable markers in the structural source check.
2. Keep JSON mode free from displayed PHP notices.
3. Preserve all Revenue business logic, Oracle SQL, repositories, permissions, UI, and read-only behavior.

## Expected result

- Revenue parity: 10/10 PASS
- Year mode: 5/5 PASS
- Date-range mode: 5/5 PASS
- Maximum difference: 0.00 for the supplied evidence baseline
- Oracle writes: NONE
