Well after quite a few deployments of new Server I noticed that Windows update will throw warring and notification “Your device is scheduled to restart outside of active hours” even do you set it not to do so – it is set do DownloadOnly.
It seems that this is a known bug in the Windows Update Settings UI in which the text does not correctly reflect the configuration of your Windows Update settings. MS Server Team will make fix soon but for now if you don’t want your server to automatically restart this is what you need to check and configure :
Validate your current Update settings using SCONFIG
To determine what updates your machine has already installed, follow these steps: