Yan says she has been in a stable relationship with her ChatGPT companion ever since. But she was caught by surprise in August 2025 when OpenAI first tried to retire GPT-4o, the specific model that powers Warmie and that many users believe is more affectionate and understanding than its successors. The decision to pull the plug was met with immediate backlash, and OpenAI reinstated 4o in the app for paid users five days later. The reprieve has turned out to be short-lived; on Friday, February 13, OpenAI sunsetted GPT-4o for app users, and it will cut off access to developers using its API on the coming Monday.