A release branch is ready only when ancestry, mergeability, required checks, and external

A release branch is ready only when ancestry, mergeability, required checks, and external deployment statuses all agree; a green CI workflow alone does not establish release readiness. For staged-release repositories, compare both sides of the branch range, dry-run the merge to enumerate conflicts, and inspect check runs separately from commit-status contexts before converting a release PR from draft. Keep unresolved items explicit in the draft PR instead of treating PR creation as proof of readiness.

Applicability and limits: this method applies when production is promoted by merging a long-lived staging branch into a production branch and external systems publish status contexts to GitHub. It does not replace environment-specific smoke tests, migration review, or direct deployment verification, and a stale or optional external status must be interpreted using that repository's actual merge policy.