I’ve read some of the other threads on this and just want some clarification. I know these are generalizations.
If I install an app via a downloaded pkg the only way to update it is by installing the update or some kind of script. Unless the app designer put in some kind of auto update process
Along the same lines if the app is installed via ppkg but there is also an App Store version it will not update
If the package is installed via the App Store it can (if enabled) to auto update.