If you return a ticket, how long does it stay on your schedule for?
Until it's returned.
It doesn't actually stay in your schedule, so you can sign up for something else.
The schedule does take a bit of time to update, at least right during this initial rush.
Director of Events
Gen Con LLC
Ok. I processed the return and got a confirmation email but it's still preventing me from getting tickets to another thing
It should not be, make sure to double-check the error message you are receiving when trying to sign up for another event. It is very likely to be another event in your schedule.
If it persists, email customer service and include your account ID and the ID of the event you are trying to cancel and the ID of the event you are trying to register for in its place so we can check both your event and the events in question.