GPT-5.5 is rolling out to Plus, Pro, Business, and Enterprise users in ChatGPT and Codex, and GPT-5.5 Pro to Pro, Business, and Enterprise users in ChatGPT The Verge 2026-04-23 Codex, Pro, Business, GPT-5.5, GPT-5.5 Pro to Pro, Business, ChatGPT Related Coverage OpenAI briefs US, allies on new cyber AI model Tech in Asia · Grace Priscilla Teo OpenAI Says Its New GPT-5.5 Model Is More Efficient and Better At Coding Slashdot · BeauHD