Is the attendee cap a cap of the total attendees in a month, total attendees in a given meeting, or total attendees for the plan?

The cap is on the total unique attendees for each meeting. After you end a meeting, the attendee count resets and you can give the meeting to another set of attendees (up to the attendee cap as shown here) This is displayed on the top-right of the presenter view as a silhouette. Click on the green figure to see the “total attendees” (a gray figure.) 

So, for example, with a 75 limit, you can give a meeting to 75 people, end that meeting and then give a meeting to another 15 people, for a total of 90 different people attending. The total attendees are for anyone who accessed the meeting (instead of just the current attendees.) Start a new meeting to reset the counter.

If you get more than 25 attendees on the free account, late attendees will not be able to access the meeting.
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