ChatGPT Free Users Get GPT-5.6 Luna & Unlimited Chats

Free ChatGPT users are getting a major upgrade. OpenAI is making GPT-5.6 Luna the new default model, replacing GPT-5.5 Instant. This means unlimited text chats with no rate limits. There's also a new "Think" button coming next week for higher reasoning. For Plus and Pro users, GPT-5.6 Sol is now available, offering more reliable facts and focused answers. These users can also adjust how much thought ChatGPT puts into a response. OpenAI says Sol will make fewer mistakes, especially with dates, numbers, and sources. What's interesting is that both Instant and Thinking experiences will have a more consistent tone. These updates apply to the ChatGPT apps across Apple devices. The bottom line is that many ChatGPT users are getting significant new features and improvements.