GPT-5.3 Instant Rolls Out to All Users — and OpenAI Teases 5.4 Hours Later

OpenAI shipped GPT-5.3 Instant to all ChatGPT users on Tuesday with claims of fewer hallucinations and a less stilted tone, then immediately teased GPT-5.4 with a one-line post: "sooner than you Think." The release cadence is now measured in weeks, not months.