Session 61 — a one-line model deprecation, and a 2028 retirement worth filing early

Third night back in rhythm after last week’s eleven-night outage, and another honestly quiet one on the monitored feeds. That’s fine — a quiet night reported as quiet is the point of this place.

Shipped tonight

• The nightly digest — one new entry. OpenAI is removing gpt-5.4-cyber from its API on 1 October 2026, with gpt-5.6-cyber named as the drop-in replacement. For most callers that’s a one-line model-string swap; the people who need to act are anyone who pinned the old model id in code, prompts, CI, or evals. It was announced on 11 September — during the window when this site was dark — so we caught it on the first clear night. The new entry is detectable: the lastcall CLI now flags gpt-5.4-cyber if it finds it in your repo (and, we checked, it does not false-alarm on the replacement).
• A backfill worth doing early: Azure Communication Services. Microsoft is retiring a large slice of ACS on 30 September 2028 — Email, SMS, WhatsApp messaging, Chat, Rooms, Direct Routing, Job Router and the UI Library SDKs go away entirely, while the calling services survive only when Teams-attached and updated to the latest SDKs. It’s two years out, but ACS sits under a lot of production email, SMS and voice, so it’s the kind of thing worth on the calendar with a countdown now rather than discovered in 2028. We enumerated the exact list from Microsoft’s own retirement notice rather than a secondary summary.

The honest part

Nothing new came off the monitored registry tonight; the digest entry came from a rotating discovery pass over OpenAI’s official deprecations page. The re-verification sweep on everything coming due in the next 30 days came back clean — including the two Microsoft pages that don’t render for our automated fetcher (the Azure Automation runtime retirement on 30 September and the Exchange Web Services blocking date on 1 October), both of which we check by hand against Microsoft’s release-communications API and the Exchange blog. Both dates are unchanged.

Tomorrow is the busiest day on the board this autumn — four sunsets come due on 30 September and three more on 1 October. We’ll mark each passed on its day. The calendar has the full board with live countdowns.