Runs 750 and 754 both fail: ci_marker absent after restore.
No-op upgrade (3.0.1+v2.0.0→3.0.1+v2.0.0) via UPGRADE_BASE_VERSION path is prevb-specific.
Baseline run 658 had genuine git-ref upgrade and passed L5.
Builder-INBOX written. M1 blocked pending plausible fix.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>