Butkhuzi Legacy Retirement Decision

Rollback Window Closure Decision

Decision: CLOSE rollback window now.

Rationale:

• Primary runtime svc-butkhuzi has been stable since Sprint 79 live cutover (March 13, 2026).
• No rollback incidents have occurred in the stabilization period.
• Parity verification confirmed in Sprint 78, live observations in Sprint 79 showed no mismatches.
• Ownership hardened in Sprint 81, establishing clear primary/fallback boundaries.
• Migration ownership transferred to svc-butkhuzi in Sprint 82.
• Team confidence in primary runtime is established.

Why not keep temporary:

• Indefinite fallback drift avoided; stabilization period exceeded 2 weeks.
• Legacy residue removed to prevent future confusion.