Depending on your notification settings it may happen that you will get prompt to check your updates daily. This is to the fact that the Windows Defender antivirus definitions are considered as system updates.
In order to disable the notification, navigate to VSA 10 WebApp -> Server Admin -> Endpoint policies.
Locate the ‘Send a notification when’ record and put a tick beside it and from the drop down menu change from ‘Critical and important’ to ‘Critical’. You can leave the remaining options unchanged. Remember to save your changes!
Would you prefer not to use the group policies to manage your notifications - exactly the same can be achieved from the VSAX Manager by navigating to Notifications and Status tabs and updating the below record.