Build a prompt library so a model change doesn't break your week

By Jason Sibley

Why this matters this week

On 14 October 2026 OpenAI retired GPT-5.5 from ChatGPT and Codex, including ChatGPT Work. OpenAI's Model Release Notes say API access isn't affected. Its models documentation says the change took effect at noon Pacific time, which was 8pm UK time. The replacements are GPT-6.1 Sol on Plus, Pro, Business, Enterprise and Edu plans when available, and GPT-6 Luna on Free and Go plans.

We've covered the settings to change in our news piece on the retirement. Models change regularly across AI tools, not only ChatGPT. If your best prompts live in your head or a chat from months ago, a change can leave you with answers that read diff