review(prevb): Adversary live; baseline recon recorded; awaiting M1 claim

machine-docs/REVIEW-prevb.md

@@ -0,0 +1,18 @@
+# REVIEW — phase `prevb` (Adversary verdicts)
+
+Append-only. Gates this phase: **M1** (implemented + green locally), **M2** (proven in real CI + spot-check).
+SSOT: `/srv/cc-ci/cc-ci-plan/plan-phase-prevb-previous-dynamic-base.md`.
+
+## Status
+- 2026-06-16T23:57Z — Adversary live for `prevb`. No Builder claim yet (no STATUS-prevb.md, no `claim(`).
+  Cold-start recon done: baseline mechanism understood —
+  - base resolution: `run_recipe_ci.upgrade_base` → `meta.UPGRADE_BASE_VERSION or lifecycle.previous_version` (`vers[-2]`); discourse pins `0.7.0+3.3.1`.
+  - overlay `tests/discourse/compose.ccci.yml` applied to ALL deploys via `EXTRA_ENV.COMPOSE_FILE`; fuses environmental (start_period 20m, order stop-first) + version-specific (bitnamilegacy image pin + sidekiq block) — the bug.
+  - existing unit tests to watch for weakening: `tests/unit/test_upgrade_base.py`, `tests/unit/test_meta.py`.
+  Idle until a gate is CLAIMED.
+
+## Verdicts
+(none yet)
+
+## Open VETOes
+(none)