Yes, but it depends on the plan you choose.
The Plus plan remains active for 7 days from your event date (i.e. - the time in which guests can still upload new photos/videos), and the Pro plan remains active for 30 days.
For example, if you upgrade to the Pro plan today, and your event starts on the 1st of August - your event will remain active till the 1st of September.
So if your event is more than one day, we suggest upgrading to one of the paid plans, according to the number of days you need.