OpenAI (and most LLM providers) allow model version pinning for exactly this reason, e.g. in the case of GPT-4o you can specify gpt-4o-2024-05-13, gpt-4o-2024-08-06, or gpt-4o-2024-11-20.
Yes, and they don't make snapshots for chatgpt-4o-latest, but they made them for GPT 4.1, that's why 4.1 is only useful for API, since their ChatGPT product already has the better model.