OpenAI maintains clear dominance in advancing its GPT model family, having released GPT-6 Astra in early September 2026, followed quickly by GPT-6 Sol and Luna on September 22 and then GPT-6.1 Sol at DevDay on September 29. These updates emphasize improved coding, agentic workflows, computer use, and cost efficiency in the Sol tier, building directly on the GPT-5.6 Sol/ Terra/ Luna structure introduced earlier in the year after regulatory reviews. No other lab has released or announced a GPT-branded model, and OpenAI's rapid iteration—driven by large training runs, alignment work, and tiered pricing—keeps the next 6.2+ Sol release squarely in its hands. Traders focus on OpenAI's internal roadmap signals, competitive benchmarks against models like Claude, and any delays from safety testing or government oversight as the key variables.