Hello @E C ,
Maybe it already checked the requirements somehow because it says "Upgrade to Windows 11 is ready".
You should try to click the "Download and Install" button, it should check the requirements.
When I has upgrading to Windows 11, it was like your situation, but backwards, the pc health check had the check button, but there was no "Upgrade to Windows 11 is ready" message in Windows update, and I used the upgrade tool that you can download for free on the official Microsoft site:
https://www.microsoft.com/en-us/software-download/windows11 (To download this tool, you need to expand the "Before you begin" thing under "Windows 11 Installation Assistant" and read it, then click the "Download Now" button, then launch the EXE file and you will be guided to install Windows 11).
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