GPT-5.5 Instant is rolling out as the default ChatGPT model for all users, with personalization improvements for Plus/Pr

GPT-5.5 Instant is rolling out over the next two days as the default model to all ChatGPT users, and as ‘gpt-5.5-chat-latest’ in the API. Personalization improvements are rolling out to Plus and Pro users on the web, and soon on mobile. Memory sources are rolling out across all