What changed
OpenAI’s October 8 API changelog adds Ultrafast processing for GPT-6.1 Sol in the Responses API, subject to rate limits. Its separate ChatGPT and Codex changelog describes Ultrafast access in Codex and ChatGPT Work for eligible plans and workspaces.
Why the distinction matters
An API feature announcement is not a promise that the same control appears in every chat app. Check the product you actually use, its plan rules, and the processing price before selecting a faster option. Faster output also does not remove the need to check the answer.
Our coverage boundary
We verified the two official changelogs and have not measured the speed difference. This is a processing-mode update, not a claim that a new Sol model launched on October 8. Current provider documentation remains the place to confirm access and charges.