Hi @Søren Bonefeld , it looks like I am having the same problem that you describe.
I have noticed that in my case the UWF configuration is messed up (multiple C: drives were protected, likely a side effect of image preparation).
However, even after cleaning up the configuration, I experience unexpected file downloads, I got a notification alert which said "Windows is downloading updates".
I do not understand why updates are running on this system if updated have been globally disabled, according to IoT Enterprise documentation, with the policy Computer Configuration\Administrative Templates\Windows Components\Windows update\Configure Automatic Updates set to disabled.
Did you manage to get to the bottom of the unexpected updates?
@Sean Liming Do I really have to manually disable the Windows Update scheduled task? Will UWF service mode still work then?