Mandatory rule
A CSC must not be activated without a valid post_office_code.
Why it matters
- Correct routing and branch reporting.
- Reduces disputes and wrong assignment issues.
- Helps audits and support to be deterministic.
Checklist
- post_office_code is present and correct (not blank).
- Branch office assignment is correct.
- If any mismatch, stop activation and escalate with booking_reference (if any).