Copilot Pro subscription and Opus models

### Describe the bug

During today (2026-04-21), I lost the ability to use any Opus model in both GitHub Copilot CLI and VS2026. Is this a bug?

If it is not, then I object to this. I do not mind the request multiplier, but to stop me using it altogether when I have had access to it for a while now on my yearly paid subscription, is just fraud.

Please re-access this decision.

### Affected version

v1.0.34

### Steps to reproduce the behavior

Use the /model. They are now moved under "UPGRADE".

### Expected behavior

To be able to select any Opus model, even with the multiplier. That is how it worked until today.

### Additional context

_No response_

The issue identifies the /model entry point and affected version v1.0.34, but no source file or test. Start by reproducing the model list in GitHub Copilot CLI with a Copilot Pro subscription and determine whether the Opus restriction is intentional; done means the entitlement behavior is restored or the decision is clearly documented.

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