Hi, @Mike D
Thank you for posting in Microsoft Q&A forum.
The reason for the error "Instance has state: Local, NoRebootRequired" is that the Visual Studio instance is in a local state and does not require a reboot.
To resolve this issue, you may try closing all Visual Studio-related processes running on your machine, rebooting the machine to ensure a clean state, and then attempting to install the Visual Studio update again.
For your reference:
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