4.5 and o3 are being retired, as long as the API still works, developers can breathe a sigh of relief

OpenAI announced in the ChatGPT update log that GPT-4.5 and OpenAI o3 will be retired from the web and mobile platforms to focus resources on the GPT-5.5 series (Instant, Thinking, Pro). Timeline: GPT-4.5 will be phased out after a 30-day transition on June 27, 2026; OpenAI o3 will be phased out after a 90-day transition on August 26, 2026. Paid users before the deadline can still select them in settings; API remains unaffected, and developers can continue to use these two models.