Document extension 119 placeholder plan

notes/2026-03-21-119-placeholder.md

+# 2026-03-21 Extension 119 Placeholder
+
+Extension `119` is intentionally retained as a placeholder and reminder.
+
+Current state:
+- old `119` hardware is dead
+- active ring groups no longer ring `119`
+- this avoids repeated `IAX2` `Subscriber absent` notices in the Asterisk console
+
+Future plan:
+- `119` should return as a `PJSIP` endpoint, not `IAX2`
+- expected deployment is behind the RV travel router over the existing VPN design
+- do not whitelist dynamic Starlink public IPs directly; allow the VPN subnet instead
+
+Ring-group cleanup applied on the live PBX:
+- `600`: removed `119`
+- `606`: removed `119`
+- `609`: removed `119`
+- `610`: removed `119`
+- `611`: removed `119`