The time you and your guests can upload photos and videos is called active time. This starts when your event is marked as started and guests actively begin uploading (not just test uploads from the event owner or one or two guests).
Here’s the active time for each plan:
Free Plan: 24 hours
Plus Plan: 30 days
Pro Plan: 3 months
Once the active time ends, your event is marked as ended, and no more uploads can be made.