diff --git a/BACKLOG-conc.md b/BACKLOG-conc.md
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+# BACKLOG — sub-phase conc
+
+## Build backlog
+
+- [ ] P1 lock-lifetime hardening: prctl PDEATHSIG + ppid race check + SIGTERM handler →
+      teardown funnel + signal.alarm(3600) hard deadline; .drone.yml setsid/trap wrap;
+      PEP 446 comment on lock open()
+- [ ] P2 flock-probe janitor: acquire_app_lock(domain) at register_run_app's call site;
+      janitor probes per-domain lockfiles (acquired→reap under probe lock, held→leave,
+      >120min mtime→warn); delete registry symbols
+- [ ] P3 per-run ABRA_DIR: /var/lib/cc-ci-runs/<build>/abra with servers+catalogue symlinks,
+      fresh recipes/; fetch_recipe = plain clone; delete acquire_recipe_lock; route harness
+      recipe paths through ABRA_DIR
+- [ ] P4 config cleanup: remove concurrency.limit from .drone.yml; maxTests is the single knob
+- [ ] tests/concurrency suite (19 cases, real-kernel flock, explicit invocation only)
+- [ ] P5 docs/concurrency.md rewrite to the new model
+- [ ] M1 claim (branch complete, both suites + lint green)
+- [ ] M2: merge to main after M1 PASS, push build green, live verification a–d
+
+## Adversary findings
+
+(adversary-owned)
diff --git a/JOURNAL-conc.md b/JOURNAL-conc.md
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+# JOURNAL — sub-phase conc (Builder, append-only)
+
+## 2026-06-10 — bootstrap
+
+Read concurrency-restructure-full-plan.md (SSOT) + plan.md §6.1/§7/§9. Oriented on the code:
+
+- `runner/harness/lifecycle.py` — recipe flock (l.46), registry (l.65–97), deploy_app
+  registration (l.283), teardown unregister (l.723), three-way janitor (l.726).
+- `runner/run_recipe_ci.py` — `acquire_recipe_lock` call site (l.843), `fetch_recipe` (l.140,
+  rm-rf + reclone of the shared tree), janitor call sites (l.600 quick, l.932 cold).
+- `.drone.yml` — recipe-ci step runs `cc-ci-run runner/run_recipe_ci.py` bare (P1 wraps it),
+  `concurrency.limit: 2` (P4 removes).
+- Greps for P3 fallout: `~/.abra/recipes` referenced in abra.py (recipe_checkout,
+  has_lightweight_version_tags, recipe_head_commit, recipe_versions), generic.py:28,
+  lifecycle.prepull_images, run_recipe_ci (fetch_recipe, snapshot_recipe_tests, comment),
+  warm_reconcile.py:202 (runs OUTSIDE per-run context — keeps default), and
+  tests/ghost+discourse install_steps.sh (`${HOME}/.abra/recipes/...` — these run INSIDE a
+  run and copy compose.ccci.yml into the deploy tree, so they must resolve the per-run dir).
+- `~/.abra/servers/...` paths are unaffected by design (servers/ is symlinked to the canonical
+  /root/.abra/servers, so both resolutions land on the same file).
+
+Working setup: state files on main in this clone; code on branch `restructure/concurrency`
+via a git worktree at ../cc-ci-conc; test runs on the cc-ci host via /root/builder-clone
+(`cc-ci-run -m pytest ...`, `nix develop .#lint`).
diff --git a/STATUS-conc.md b/STATUS-conc.md
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+# STATUS — sub-phase conc (concurrency restructure)
+
+Plan: /srv/cc-ci/cc-ci-plan/concurrency-restructure-full-plan.md (SSOT for this phase)
+
+## Phase state
+
+- Phase: conc — concurrency restructure (P1–P5 + tests/concurrency)
+- Builder branch: `restructure/concurrency` (code lands there; main untouched until M2 merge)
+- In flight: P1 (lock-lifetime hardening)
+- Gate: none claimed yet
+
+## Gates
+
+- M1 (implementation verified): NOT CLAIMED
+- M2 (merged + live-verified): NOT CLAIMED — blocked on M1 PASS
+
+## Blockers
+
+(none)