Best practice for scoping "Mac Appstore Apps" with VPP licence

New Contributor II

The setup is as follows:
I have a couple of apps, that are available on the Mac Appstore with a volume purchasing license attached and I want to distribute them to all the laptops.

I have the option the following options enabled:
"Schedule Jamf Pro to automatically check iTunes for app updates"
"Automatically Force App Updates"

The problem is as follows:
I have users that already have those apps installed through a different channel (Brew, App store, DMG downloaded from the internet).
So I don't know how to scope this policy correctly so that all computers that have installed the app through jamf receive the updates, but I don't interfere with other installations.

As a bonus question: What happens when I scope an app to a device, that already has the app installed say through brew?