GPT-5.4 and GPT-5.4 mini leave Codex on August 31

GPT-5.4 and GPT-5.4 mini will no longer be available in Codex for ChatGPT sign-in from August 31, 2026. They stay on the API. Replacements named were GPT-5.6 Terra and GPT-5.6 Luna.

Who is affected:

Codex users signed in with ChatGPT who use GPT-5.4 or GPT-5.4 mini.

Action needed:

Update workspace defaults, saved settings and scheduled tasks before August 31.