We’re rolling out GPT-5.5 Instant Mini in ChatGPT. It replaces GPT-5.3 Instant Mini as the fallback model users reach after hitting their GPT-5.5 Instant or Auto rate limits. Because it serves as a fallback, it won’t appear in the model picker. This update does not affect the API or Codex.Compared with GPT-5.3 Instant Mini, GPT-5.5 Instant Mini better tracks evolving user intent, calibrates tone, and avoids repetitive or overly structured responses. Testing also showed stronger personalization and fewer factual issues.