OpenAI launches GPT-6 Sol and Luna: cheaper, faster and with fewer factual mistakes
On 22 September 2026 OpenAI released GPT-6 Sol (complex/coding) and GPT-6 Luna (high-volume clerical) at roughly half GPT-5.6 prices; Sol claims about half the factual mistakes versus its predecessor and Astra-like reliability at lower cost, with the IPO delayed to 2027.