@Teresa_Cyrus thank you...that PDF is definitely more comprehensive than what's on the page. I'm sure all of the info is available across different MS pages. However, nowhere in either document is there a specified limit to the number of calendars a user may create. Since Exchange doesn't generally allow self-serve calendar creation, there's no stated limit in the Exchange documentation, either. I'm certain that a limit exists (there is ALWAYS a limit), but it's just not shown anywhere.
In another (developer-licensed) tenant, I was able to create 12 calendars using a 'regular' user account. Honestly, I can't see a valid reason for a normal user to create that many (or more), but we have two people in our production tenant who are getting an error message (a generic "error has occurred...try again later" message) when trying to create a 4th calendar (they already have 3, this appears when trying to create another).
