diff --git a/CHECKLIST.md b/CHECKLIST.md
index cdeca96b..740d8711 100644
--- a/CHECKLIST.md
+++ b/CHECKLIST.md
@@ -5,7 +5,7 @@ at the end of every session. Pair with
 [`docs/references/espectre-gap-analysis.md`](docs/references/espectre-gap-analysis.md)
 for the technical detail behind each line.
 
-Last sweep: **2026-05-17**, branch `feat/ota-rssi-mobile`, head `e4204595`.
+Last sweep: **2026-05-17**, branch `feat/ota-rssi-mobile`, head `eec3ca6c`.
 
 ---
 
@@ -22,8 +22,15 @@ Last sweep: **2026-05-17**, branch `feat/ota-rssi-mobile`, head `e4204595`.
 - [x] **ADR-103** Universal threshold via baseline-CV normalization
 - [x] **ADR-104** Per-subcarrier drift channel (off-axis presence)
 - [x] **ADR-104** NBVI Step 3 FP-rate validation (K ∈ {6,8,10,12,16,20})
+- [x] **ADR-104** Per-sub drift exposed in WS `node_features[].drift_score`
+      + raw.html sparkline per node (commit eec3ca6c)
+- [x] **ADR-104** Baseline staleness watch — warn when on-disk baseline
+      > 4 h old AND drift consistently fires during `absent` periods
+      (commit eec3ca6c)
 - [x] **ADR-105** Drop all synthetic data from runtime
   ([signal_field, pose_keypoints, persons, fake confidence — all gated)
+- [x] **ADR-105** `n_aps_used: u8` uniform field on `enhanced_motion` +
+      `enhanced_breathing` (commit 598a4b2f)
 - [x] **ADR-106** Full complex CSI in WS (`amplitude` + `phases` + meta)
 - [x] **ADR-106** Built-in CSI keepalive (managed `ping` per sensor)
 - [x] **ADR-106** Server-side µs `timestamp_us`
@@ -61,18 +68,12 @@ Last sweep: **2026-05-17**, branch `feat/ota-rssi-mobile`, head `e4204595`.
 
 ### High value, low effort
 
-- [ ] **Per-sub delta sparkline in `raw.html`** — operator sees off-axis
-      drift channel firing in real time. ~30 min. (ADR-104 open)
 - [ ] **`POST /ota/recalibrate`** — clear gain-lock NVS via REST,
       no USB needed. ~30 min FW + OTA. (ADR-108 open)
 - [ ] **Track AP MAC in NVS alongside gain-lock** — auto-invalidate
       stale values on AP swap. ~1 h FW + OTA. (ADR-108 open)
-- [ ] **Per-subcarrier baseline AGE check** — flag for re-calibration
-      when channel slowly drifts. ~1 h. (ADR-104 open)
 - [ ] **Tailscale-target in NVS** — sensor stream keeps working when
       Mac roams networks. ~30 min provision + reflash. (ADR-100 open)
-- [ ] **`n_aps_used` field in `enhanced_*`** — let consumers know
-      when multi-AP pipeline ran on a single sensor. ~30 min. (ADR-105 open)
 
 ### High value, medium effort
 
diff --git a/docs/adr/ADR-104-per-subcarrier-drift-presence.md b/docs/adr/ADR-104-per-subcarrier-drift-presence.md
index f5de2ab8..474cd684 100644
--- a/docs/adr/ADR-104-per-subcarrier-drift-presence.md
+++ b/docs/adr/ADR-104-per-subcarrier-drift-presence.md
@@ -136,21 +136,31 @@ conditions where a previously-clean subcarrier picks up interference.
 
 ## Open Items
 
-* **Per-subcarrier baseline AGE check** — the per-sub vector reflects
-  the channel at calibration time. As the channel slowly drifts (other
-  WiFi clients on the AP, temperature, etc.) the per-sub baseline ages
-  faster than the broadband-mean baseline. Need: if `last_written_sec_ago`
-  > N hours AND drift consistently > threshold → flag for
-  re-calibration. Defer to a future ADR-109.
-* **Per-subcarrier delta in UI** — `raw.html` only shows broadband
-  bars + global classification. A small "drift" sparkline per node
-  would let the operator see the off-axis channel firing. ~30 min.
 * **Phase-domain drift** — currently amplitude-only. Phase delta vs
   baseline phase would catch even subtler movement (chest-wall sub-mm
   motion during breathing). Requires phase baseline in `baseline.json`,
   which the recording script doesn't yet save. ~1 h script + ~30 min
   server.
 
+## Closed
+
+* **Per-subcarrier baseline AGE check** — `baseline_staleness_watch`
+  background task warns when on-disk baseline is older than
+  `--baseline-stale-age-sec` (default 4 h) AND per-sub drift exceeds
+  1.5× presence threshold for ≥3 consecutive 5-min ticks while the
+  classifier reports `absent`. Rate-limited via
+  `--baseline-stale-warn-cooldown-sec` (default 1 h). Independent
+  from `auto_recalibrate_task`: that path needs a quiet room; this
+  one fires when the operator is *in* the room while the channel
+  itself has shifted. (commit eec3ca6c)
+* **Per-subcarrier delta in UI** — `raw.html` now shows a per-node
+  drift sparkline below the RSSI/broadband trace, fixed Y range
+  [0, 0.30] with dashed presence (0.10) and warning (0.15)
+  thresholds. Numeric "drift" stat pill in the per-node header.
+  Backed by a new `drift_score: Option<f64>` field on
+  `PerNodeFeatureInfo` (skip-if-none — distinguishes "no per-sub
+  baseline loaded" from "loaded and stable at 0.0"). (commit eec3ca6c)
+
 ## References
 
 * ADR-101 — broadband classifier; this ADR adds a parallel channel.
diff --git a/docs/adr/ADR-105-no-synthetic-data-in-production-runtime.md b/docs/adr/ADR-105-no-synthetic-data-in-production-runtime.md
index 131bda30..7df8d76b 100644
--- a/docs/adr/ADR-105-no-synthetic-data-in-production-runtime.md
+++ b/docs/adr/ADR-105-no-synthetic-data-in-production-runtime.md
@@ -170,9 +170,14 @@ classification        absent / present_still / present_moving / active per ADR-1
 * **Real signal_field** via multistatic fusion — when ≥ 2 nodes are
   active, `MultistaticFuser` can produce a physically meaningful
   spatial map. ADR-104 will cover wiring it through.
-* **Honest `enhanced_*` fields** — when the multi-AP pipeline runs
-  on a single sensor it still emits scores. Should add a
-  `n_aps_used` field so consumers know whether to trust them.
+
+## Closed
+
+* **Honest `enhanced_*` fields** — both `enhanced_motion` and
+  `enhanced_breathing` now carry a uniform `n_aps_used: u8` field
+  alongside the legacy `contributing_bssids` / `bssid_count`
+  counts. Consumers can gate on `n_aps_used >= 2` before trusting a
+  multi-AP enhancement. (commit 598a4b2f)
 
 ## References