I have one Ubuntu one Windows at home, Windows made me update again today (last time a week or two ago) - took forty minutes. Next PC will have Ubuntu on it too.
After disabling the Windows Update service in the Computer Management Console, click on the Recovery Tab. There, turn first three options to "Take No Action." Else, the service will reactivate itself after a while.
This way, you control when you want to update.
Note: If you use Defender, manually turn on the Update Service when you want to update the definitions.