How to prevent Windows 11 Update / Upgrade check being installed

Windows 10 silently installs the new Windows 11 upgrade check through windows update. If you remove it, it gets reinstalled again.
To stop it from being installed, you can open regedit and go to the key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PCHC
And create a String named PreviousUninstall with the value 1
PreviousUninstall = 1

This will prevent the installation of the Upgrade check once and for all.