This session established the actual release state and completed the crystal correction, but the board is not yet fab-ready.
- Independent audit confirmed the original USB route has four asymmetric through-vias, approximately 3.4 mm skew, variable geometry, and loose coupling. A fabrication impedance note cannot make that production-safe.
- The 32.768 kHz crystal block was rebuilt successfully: X1/C15/C16 placement and XL1/XL2 are now short, local, Top-only, and via-free.
- The USB rebuild exposed a D+/D− pin-order crossover between J1, U7, and U1. Reorienting U7 and restoring the displaced routes was launched, but I could not retrieve and independently reconcile its final report.
- The last confirmed intermediate state was commit #7214da2f with 13 airwires, so manufacturing exports were correctly withheld.
- BOM consolidation/mapping issues also still require correction before PCBA release.
Remaining release work:
- Confirm the latest live routing state and restore any remaining airwires.
- Complete USB as a Top-only, via-free, consistently coupled pair with ≤0.5 mm skew.
- Correct BOM grouping and remaining LCSC mappings.
- Run fresh independent ERC, DRC, route-layer, RF, footprint, and assembly audits.
- Generate and inspect Gerber/drill, BOM, and pick-and-place files.
Execution stopped because your ACUs ran out.