MicrosoftHi Paul_Huijbregts I have double checked the docs and found it here
https://docs.microsoft.com/en-us/microsoft-365/security/defender-endpoint/configure-server-endpoints?view=o365-worldwide#known-issues-and-limitations in the Known issues and limitations section of the first chapter.
While the article does apply for all OS, I would suggest to use the existing chapter per OS (additionally) or eventually add a note
>[!NOTE]
>- Operating system upgrades are not supported on Windows Server xxxxxx. Offboard then uninstall before upgrading.
>The installation helper script (link) provides an option to automate the offboarding and uninstall steps to make it easier to get the OS in an upgradeable state. As security monitoring will be interrupted during the upgrade period and a new machine object created, please ensure your security operations are aware of this!
I would create a PR on github, but I cannot contribute which OS would be supported in that case and which not, so I refrain to do so.
