I've noticed on a few instances of events with the same discription (mostly learn to play events) have different durations, one has two hour and another has four.
The price is the same for both and since the tickets are usually by the hour, can we assume the event length matches the ticket price?
It's probably something to contact the GM about.
Which events did you notice this with?
Gen Con LLC
Game ID: BGM1688124
and a couple Pocket Madness events.