According to Sam Altman on Twitter, OpenAI is doubling GPT-5 rate limits for ChatGPT Plus users as the model rollout completes. Plus subscribers will have the option to continue using the legacy GPT-4o model, with OpenAI monitoring usage to determine how long legacy models remain available. These updates are aimed at improving user experience and offering greater flexibility for business applications, signaling a competitive push in generative AI services and enhanced productivity tools. (Source: Sam Altman, Twitter, August 8, 2025)