Assume that Automatic Updates is enabled on a Windows 8 or Windows Server 2012-based computer. You choose the 4 - Auto download and schedule the install option, and define the frequency and time for updates to be installed in the following Group Policy setting:
However, the scheduled day and time in this policy setting has no effect. The computer still installs downloaded updates during automatic maintenance, which defaults to 2:00 AM. Additionally, the computer no longer restarts 15 minutes after installing updates. To help avoid unintended data loss, a restart timer instead begins 3 days after updates are installed, and only when you are actively using the computer and are able to see and react to the restart timer.
Computer Configuration\Administrative Templates\Windows Components\Windows Update\Configure Automatic Updates
However, the scheduled day and time in this policy setting has no effect. The computer still installs downloaded updates during automatic maintenance, which defaults to 2:00 AM. Additionally, the computer no longer restarts 15 minutes after installing updates. To help avoid unintended data loss, a restart timer instead begins 3 days after updates are installed, and only when you are actively using the computer and are able to see and react to the restart timer.