Two rows, read on the same afternoon from the two vendors that sell this model.

OpenAI's deprecations page:

gpt-4.1-nano | gpt-4.1-nano-2025-04-14 → gpt-5.6-luna October 23, 2026

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Microsoft's Azure OpenAI model retirements page:

Model Version Training retirement Deployment retirement gpt-4.1-nano 2025-04-14 No earlier than 2027-04-14 2027-10-14

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Same model. Same version string — 2025-04-14 on both. One page retired it four days ago.

The other gives it until next October. Neither page is out of date, and neither is wrong.

That is 356 days of difference on a single identifier.

The name is not the thing

The instinct is to treat gpt-4.1-nano as a fact about a model. It isn't. Retirement is a

decision made by whoever is running the inference, and this model is run by two organisations

with separate roadmaps, separate contracts and separate customers.…