OpenAI's September 2026 launches of GPT-6 Astra followed by Sol and Luna models, plus the late-September GPT-6.1 Sol update, anchor current sentiment around the company's continued control of the GPT Luna lineup. These releases delivered 50% API price cuts, improved alignment and coding benchmarks, and broader ChatGPT rollout in early October, extending Astra-level efficiencies to lower-cost tiers amid direct competition from Anthropic's Opus 5.5. Traders focus on OpenAI's development cadence, safety-driven delays for higher-tier variants like 6.1 Astra, and upcoming DevDay follow-ups or enterprise expansions as key swing factors for any 6.1+ Luna release timeline or attribution.