OpenAI has made its GPT-5.6 lightweight model Luna available without usage caps for ChatGPT free users and users on the lower-priced Go plan, but only for text conversations. Existing limits still apply to file uploads, image generation and voice chat. Luna is described as the fastest model in the GPT-5.6 lineup, though with relatively lower performance, and it adds a "Think" option that can extend reasoning time. The company also updated its flagship GPT-5.6 model Sol for Plus and Pro users, saying it has improved reliability for factual details such as numbers, dates and sources. At the same time, OpenAI delayed the release of its next-generation model Astra after internal evaluations in coding and cybersecurity showed strong capabilities that may warrant a "dangerous" rating, leading the company to pause related internal activity until tighter safety standards are completed.