[vidarh]

If you use the API, you pay for a specific model, yes, but even then there are "workarounds" for them, such as someone else pointed out by reducing the amount of time they let it "think".

If you use the subscriptions, the terms specifically says that beyond the caps they can limit your "model and feature usage, at our discretion".

[chrisjj]

Sure. I was separating the model - which Anthropic promises not to downgrade - and the "thinking time" - which Anthropic doesn't promise not to downgrade. It seems the latter is very likely the culprit in this case.