In a series of posts on X on Monday, OpenAI CEO Sam Altman said that the popularity of the company’s new image-generation tool in ChatGPT will cause unspecified product delays.

“We are getting things under control, but you should expect new releases from OpenAI to be delayed, stuff to break, and for service to sometimes be slow as we deal with capacity challenges,” Altman wrote. “Working as fast we can to really get stuff humming.”

OpenAI’s new image-generation capability arrived with much fanfare — and controversy — for its impressive ability to recreate styles like Studio Ghibli’s hand-drawn animation. Over the weekend, Altman said in posts on X that the company “hasn’t been able to catch up” since launch and that staff have worked late nights and through the weekend to “keep the service up.”

In a single hour on Monday, ChatGPT added a million new users, Altman claimed in a post. ChatGPT now has 500 million weekly users and 20 million paying subscribers, up from 300 million users and 15.5 million subscribers at the end of 2024.

In an effort to ease its capacity issues, OpenAI delayed the release of the image-generation tool for free ChatGPT users and temporarily disabled video generation for new users of Sora, the company’s suite of generative AI media tools.