diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0d69902..e3d1232 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,7 +4,30 @@ All notable changes to seismo-relay are documented here.
 
 ---
 
-## Unreleased
+## v0.31.0 — 2026-09-18
+
+**Report parity, and a second way to rescue a runaway unit.**  Two threads.
+
+The first closes out Blastware Event/FFT-Report parity: the FFT, the USBM
+RI8507 compliance chart and the sensor self-check now render on the event
+report, reverse-engineered against BE12844 (MiniMate Plus) and UM (Thor)
+events.  The sensor check is decoded for **both** series and standardized into
+the `.h5` (schema **v2**, a new `/sensor_check` group), so SFM serves it
+device-agnostically rather than decoding at report time.  The Inspector — an
+annotated hex reader for series-3 binaries — is what made the trailing-block
+structure findable, and it earned its keep by *ruling out* a stored FFT block
+and proving Blastware computes it from the samples.
+
+The second came out of a field emergency.  BE12599's connector fault drove its
+Tran channel to its trigger level, so the unit recorded back-to-back and dialed
+the office ACH server every ~75 s, unreachable the whole time.
+`bridges/ach_server.py` gained `--stop-monitoring` / `--disable-ach` /
+`--rescue`, which **invert** the recovery: instead of racing a Stop into the
+gaps between dial-outs, point the modem's Destination at our own ACH server and
+answer the call.  Proven in production the same night — the stop landed on the
+first call-in and held.  See `docs/runbooks/wedged_unit_recovery.md`.
+
+⚠ **This release owes prod a backfill** — see Migration below.
 
 ### Added
 - **Rescue-on-connect for `bridges/ach_server.py`** — `--stop-monitoring`
diff --git a/CLAUDE.md b/CLAUDE.md
index 7b74a84..67dee54 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -2,7 +2,7 @@
 
 Ground-up Python replacement for **Blastware**, Instantel's Windows-only software for
 managing MiniMate Plus seismographs. Connects over direct RS-232 or cellular modem
-(Sierra Wireless RV50 / RV55). Current version: **v0.30.0**.
+(Sierra Wireless RV50 / RV55). Current version: **v0.31.0**.
 
 Stack-level context — which repo owns what, and how the three project versions
 pair — lives in `../terra-view/docs/tmi-stack.md`, which is also loaded as
diff --git a/README.md b/README.md
index a11473c..7f384f2 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# seismo-relay  `v0.30.0`
+# seismo-relay  `v0.31.0`
 
 A ground-up replacement for **Blastware** — Instantel's aging Windows-only
 software for managing seismographs.  Supports both the **MiniMate Plus
diff --git a/pyproject.toml b/pyproject.toml
index 4b9e639..10ea7e7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "seismo-relay"
-version = "0.30.0"
+version = "0.31.0"
 description = "Python client and REST server for MiniMate Plus seismographs"
 requires-python = ">=3.10"
 dependencies = [