I am pretty sure they also boost you when you start using the app again after a period of inactivity, but not sure if the implementation/magnitude is different from the new-user bonus
It's all speculation, but they _seem_ to track a large amount of data to try and check for "new profiles" that are old users starting a new account, supposedly for 3 months after you delete your account. These are the ones I've seen commonly talked about.
