docs: close out the instruction arc — t740 corrected on evidence, registers, ledger, S-37

target-selection.md said demo-hp has no off-site tier. Measured first: pvesm list felhom-pbs on the
box returns two snapshots in demo-hp's OWN namespace (2026-07-28, 2026-08-04) against ep0's
felhom-offsite. The claim was TRUE WHEN WRITTEN and went stale when F10 resolved 2026-07-23. The
measurement is kept in an HTML comment beside the corrected sentence. This file decides which
machine may be destroyed, so the sentence was load-bearing, not cosmetic.

R-229(b) CLOSED (agent 175 -> 99 eff). R-230(b) CLOSED (symlink, proven from fresh sessions).
R-230(a) part-actioned -- three false statements fixed, WARN loop added, bulk ruling still owed.

S-37: a claim in an instruction file is checked, not trusted.

documentation/runbooks/target-selection.md

@@ -68,8 +68,34 @@ felhom-pve, and **moved off DooPlex**. This page exists because that ruling sat
 ### `demo-felhom` — N100 · **Tier 0**
 
 - **Freely:** create/destroy guests and scratch customers; reinstall the box.
-- **Care:** it carries the **PBS-DR / offsite tier** (demo-hp has none), so it is the Tier 0 box whose
-  backup chain a test can actually disturb. Prefer demo-hp, per the 2026-07-25 ruling.
+- **Care:** it carries the **PBS-DR / offsite tier** — but so does demo-hp now, so this is **no longer
+  a reason to prefer one over the other**. Prefer demo-hp per the 2026-07-25 ruling, on the ruling's
+  own grounds (it is the designated drill host), not because its backup chain is safe to disturb.
+
+<!--
+CORRECTED 2026-08-06. This line used to read "(demo-hp has none)" and was the runbook's stated reason
+for steering backup-disturbing tests at demo-felhom. It was TRUE WHEN WRITTEN and went stale when F10
+resolved on 2026-07-23; it was flagged as wrong for some time and carried anyway.
+
+Measured before editing, on the box, from the tier's own evidence rather than a config entry:
+
+  demo-hp:/etc/pve/storage.cfg   pbs: felhom-pbs -> datastore felhom-offsite, server 10.77.0.1,
+                                 namespace demo-hp, username felhom@pbs!demo-hp
+  demo-hp# LC_ALL=C pvesm list felhom-pbs
+    felhom-pbs:backup/ct/9201/2026-07-28T19:19:45Z  pbs-ct  6264034048  9201
+    felhom-pbs:backup/ct/9201/2026-08-04T19:24:16Z  pbs-ct  4637840512  9201
+  ep0:/mnt/pbs-datastore/ns/     c11  demo-felhom  demo-hp  rewalk
+
+Two snapshots, the newest two days old, in demo-hp's OWN namespace on the shared off-site datastore.
+The PBS-DR leg is what was measured here; the restic/offbox app-data leg is separately evidenced by
+R-193, whose whole subject is demo-hp's off-site app-data tier being dropped by the 2026-08-03
+rebuild and restaged.
+
+Why this mattered more than a typo: this file's job is to say which machine may be destroyed, and the
+sentence was load-bearing for that judgement — "its backup chain is not disturbable" is exactly the
+kind of belief under which a drill lands somewhere it should not.
+-->
+
 
 **Both Tier 0 boxes — the shared backup-target fence is DOWNGRADED to a cost, 2026-08-02 (D-d).** It
 read *"do not re-point either backup target"*, because these are the only two **correctly configured**