diff --git a/playbooks/nh3-extdev-althing-v3.yaml b/playbooks/nh3-extdev-althing-v3.yaml
index 4feba21..0ce8445 100644
--- a/playbooks/nh3-extdev-althing-v3.yaml
+++ b/playbooks/nh3-extdev-althing-v3.yaml
@@ -19,21 +19,26 @@
 # Rerunnable: a second run shows the install and unit steps skipped.
 
 vars:
-  wheel_src: /home/lkraven/development/althing/dist/althing_core-3.0.3-py3-none-any.whl
-  wheel_dest: /tmp/althing_core-3.0.3-py3-none-any.whl
+  wheel_src: /home/lkraven/development/althing/dist/althing_core-3.1.0-py3-none-any.whl
+  wheel_dest: /tmp/althing_core-3.1.0-py3-none-any.whl
   uv: /home/infra-ops/.local/bin/uv
   tool_dir: /opt/uv-tools
   bin_dir: /usr/local/bin
   # ⚠ Moved off nh3-dev 2026-08-28. A stale value here does not fail loudly at
   # install time — it fails in the VERIFY, which then reads as a broken deploy.
   post_office: http://10.100.50.40:8390
-  marker: PANE_SETTLE_S
-  marker_file: post_office_herald.py
+  # ⚠ A release can change more than one file — 3.1.0 changed two. One pair is not
+  # enough, and a check that asserts only half a release is a check that half-passes
+  # silently. Space-separated `file:marker` pairs; bump BOTH per release.
+  #   3.0.1  zellij.py:_PANE_ID  session_source.py:_live_pid    (pane routes)
+  #   3.0.3  post_office_herald.py:PANE_SETTLE_S               (write/submit race)
+  #   3.1.0  post_office_herald.py:POST_OFFICE_HINT  dev_launch.py:resolve_post_office
+  markers: "post_office_herald.py:POST_OFFICE_HINT dev_launch.py:resolve_post_office"
 
 steps:
   - name: Stage the v3.0.0 wheel
     upload:
-      src: /home/lkraven/development/althing/dist/althing_core-3.0.3-py3-none-any.whl
+      src: /home/lkraven/development/althing/dist/althing_core-3.1.0-py3-none-any.whl
       dest: "{{ wheel_dest }}"
       mode: "0644"
 
@@ -109,7 +114,7 @@ verify:
     shell: ALTHING_POST_OFFICE={{ post_office }} {{ bin_dir }}/postbox --handle operator handles | wc -l | awk '{ if ($1 >= 70) exit 0; else exit 1 }'
     changed_when: "false"
 
-  - name: This release's marker is present BY CONTENT, not by version string
+  - name: This release's markers are ALL present BY CONTENT, not by version string
     # forseti's own checks. A dist-info directory records what was INSTALLED, not
     # what the files CONTAIN — verify the code, not the label. Bump `marker` and
     # `marker_file` with each release rather than trusting the version bumped.
@@ -117,5 +122,11 @@ verify:
     #   3.0.3  PANE_SETTLE_S in post_office_herald.py  (the write/submit race)
     shell: |
       SP={{ tool_dir }}/althing-core/lib/python3.13/site-packages/althing
-      grep -q '{{ marker }}' "$SP/{{ marker_file }}"
+      rc=0
+      for pair in {{ markers }}; do
+        f="${pair%%:*}"; m="${pair##*:}"
+        if grep -q "$m" "$SP/$f"; then echo "  ok   $f : $m"
+        else echo "  MISS $f : $m"; rc=1; fi
+      done
+      exit $rc
     changed_when: "false"