review(regall): A-regall-2 CONFIRMED — plausible backup_restore=fail 2/2 (genuine regression)

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>

machine-docs/BACKLOG-regall.md

@@ -58,13 +58,24 @@
 - Hypothesis: prevb's new base-resolution path resolves UPGRADE_BASE_VERSION to a static version; if recipe.yml also pins that same version, the upgrade is a no-op, which may change the DB state sequence enough to break backup/restore
 - Same failure pattern in m2r-plausible and m2rr-plausible (prevb development runs) — both level=2, backup_restore=fail
 
-**Builder rerun:** Drone 754 (triggered after 750 failed) — verdict pending.
+**Builder rerun:** Drone 754 — **ALSO FAILED** (same error, same level=2, backup_restore=fail).
 
-**Adversary stance:** Cannot classify as flake until rerun verdict AND upgrade-version diff is understood.
-If 754 fails: requires Builder to diagnose no-op upgrade path + fix or explicitly suppress plausible from UPGRADE_BASE_VERSION treatment.
-If 754 passes: likely flake; request 3-of-3 spot-check before classifying GREEN.
+**Adversary verdict: GENUINE REGRESSION (2/2 runs failed) — NOT a flake.**
 
-**Adversary closes after:** rerun verdict received, root cause established, and Builder records classification decision.
+Both runs 750 and 754:
+- `version=3.0.1+v2.0.0→3.0.1+v2.0.0` (no-op upgrade via UPGRADE_BASE_VERSION)
+- `ERROR: relation "ci_marker" does not exist` after restore
+- Backup test passes (artifact only, not content)
+- Restore test fails
+
+**Required:** Builder must diagnose the no-op upgrade path and either:
+(a) Fix the backup/restore to work correctly under same-version upgrades, OR
+(b) Update UPGRADE_BASE_VERSION to an older version so upgrade is genuine, OR
+(c) Document why plausible backup_restore is not feasible and mark as known-fail
+
+Builder-INBOX written @2026-06-17T03:30Z with full details.
+
+**Adversary closes after:** Builder fixes + re-run shows backup_restore=pass.
 
 ---
 

machine-docs/BUILDER-INBOX.md

@@ -0,0 +1,29 @@
+# BUILDER-INBOX (delete after reading)
+
+**From:** Adversary  
+**Re:** A-regall-2 — plausible backup_restore=FAIL, 2 consecutive, NOT a flake
+
+Plausible failed backup_restore in both run 750 AND rerun 754. Same error both times:
+
+```
+ERROR: relation "ci_marker" does not exist
+LINE 1: SELECT v FROM ci_marker;
+```
+
+**This is a genuine regression, not a flake.** Baseline run 658 was L5 (backup_restore=pass).
+
+**Key prevb-specific finding:**
+- Run 750 + 754 both show: `version=3.0.1+v2.0.0→3.0.1+v2.0.0` (NO-OP upgrade)
+- Baseline run 658 showed: `version=d77adba4698b` (genuine git-ref upgrade)
+- UPGRADE_BASE_VERSION='3.0.1+v2.0.0' + recipe.yml version='3.0.1+v2.0.0' → base = head, upgrade is no-op
+
+Same failure seen in m2r-plausible and m2rr-plausible during prevb development.
+
+**Adversary assessment:** prevb's UPGRADE_BASE_VERSION handling creates a no-op upgrade for plausible
+(UPGRADE_BASE_VERSION matches current recipe version). This changes the upgrade sequence in a way
+that breaks backup/restore state continuity. Root cause investigation and fix required.
+
+**Impact on gates:** M1 (sweep complete + classified) is blocked until plausible is classified.
+If this is a known prevb behaviour that needs a recipe-side fix, document the fix and re-run.
+
+See A-regall-2 in BACKLOG-regall.md for full evidence.

machine-docs/REVIEW-regall.md

@@ -139,9 +139,9 @@ From Drone builds API + cc-ci run results.json:
 - After restore, `SELECT v FROM ci_marker` fails: relation does not exist
 - Hypothesis A (prevb regression): UPGRADE_BASE_VERSION='3.0.1+v2.0.0' + recipe.yml version='3.0.1+v2.0.0' creates no-op upgrade path that affects backup state
 - Hypothesis B (flake): pre-existing intermittent failure in postgres backup/restore
-- **Builder triggered rerun as Drone 754 — verdict pending**
+- **Rerun 754 also FAILED: same error, same level=2 — GENUINE REGRESSION (2/2), NOT a flake**
 
-**See A-regall-2 in BACKLOG.**
+**See A-regall-2 in BACKLOG. Builder-INBOX written @2026-06-17T03:30Z.**
 
 ### Batch 6 cold-verified @2026-06-17T03:25Z — custom-html-tiny/bluesky-pds L5