The company is letting Free and Go users access unlimited text chats, with no text-based rate limits. For Plus and Pro users, GPT–5.6 Sol is more reliable with facts and gives more focused answers. OpenAI says GPT–5.6 Sol will avoid unnecessary formatting and will offer a "helpful correction when simply agreeing wouldn't be useful." Plus and Pro users have access to the updated GPT–5.6 Sol and the slider in ChatGPT starting today. GPT–5.6 Luna is becoming the default model for Free and Go users this week, with unlimited text chats and the Think button coming next week.