OpenAI cut GPT-5.6 API prices up to 80% in July 2026 and replaced Priority Processing with Fast mode

OpenAI cut GPT-5.6 API prices up to 80% in July 2026 and replaced Priority Processing with Fast mode Summary. On July 30, 2026 OpenAI cut the API price of GPT-5.6 Luna by 80%, to \(0.20 per million in