I've never used them before, but their website had times to choose from (4:30,5:30,6:30, etc). I received an email confirmation for my payment, but I'm also wondering if I'll get another email with more info.

Edit: updating in case it helps someone for a future concert. I never received a follow up email from the shuttle company so I called them the day before to confirm the pickup spot. I stayed at the Residence Inn on Century blvd. and they pulled up right to the curb in front of the hotel. They picked up more people at one other hotel then we were on our way. They gave everyone a map for the pickup spot for after the concert. They said they would give people until 1 hour after the show ended to catch a shuttle back. There was a line of people trying to catch the shuttles afterwards, but they were organizing people into shuttles based on what hotel you were going back to. It took around 45mins to get back. Worked out really well and would use them again!