I had an issue recently where a customer running with a 50-user Enterprise Hosted Confluence had problems with Team Calendars complaining about the license not matching the number of users that Confluence had. Technically that's true, because a "50 user" license for EHSP instances is actually 51, to account for our support account.

This particular customer had been running Team Calendars previously, and it wasn't until the update to 2.2.1 that this problem reared its head.