OpenAI's rapid iteration on its Sol-tier models drives current trader focus, with GPT-6.1 Sol launching September 29, 2026—just one week after GPT-6 Sol and Luna—delivering near-Astra performance on agentic coding, computer use, and professional workflows at roughly one-fifth the cost. This follows the GPT-5.6 Sol family’s general availability in July after a U.S. government-requested limited preview, highlighting efficiency gains, new "max" and "ultra" reasoning modes, and expanded agent capabilities like Dots introduced at DevDay 2026. Competitive pressure from Anthropic’s Claude models and pricing reductions (50% lower API rates for Sol and Luna versus prior tiers) reinforce OpenAI’s lead in the Sol capability band, though regulatory scrutiny on high-risk uses and the pace of frontier releases create uncertainty around the exact timing and naming of any 6.2+ update.