What happens when some limits are reached ? Do I receive a notification, is the app blocked and nobody can use it, am I automatically billed for the next plan etc. ?
I am referring to limits for the number of users, the number of updates etc.
You should get warning email if you are approaching your limits, but once you exceed them, there is usually a banner on the screen saying limits have been exceeded. It may disable the app. I don’t remember for sure.
If you exceed user limits, it shouldn’t allow any additional users to sign in. As for updates, you can enable ‘Pay as you go’ to be automatically billed for additional updates, or you can stick with fixed updates, so it will stop working once the update counts are exceeded.