OpenAI has updated GPT-5.6 Sol in ChatGPT and is changing how free users access its models, according to The Decoder.
The report says Sol now gives more focused responses and includes a reasoning slider that lets users choose how deeply the model should think. Free users are expected to get unlimited text chats with the smaller GPT-5.6 Luna, plus a button that lets Luna spend more effort on harder questions.
The shift shows a familiar product tradeoff. OpenAI can make ChatGPT feel less restricted for casual users by giving them unlimited access to a smaller model, while keeping heavier models and deeper reasoning behind tighter controls. That helps manage cost and capacity without removing the basic chat experience.
The important limitation is capability. The smaller model is described as falling short of OpenAI’s larger systems, so “unlimited” does not mean equal performance. Users will still need to understand which model they are using when accuracy, reasoning depth, or coding reliability matters.