I think the basic procedure is the same but the actual times vary depending on time of year, crowd and the mood of the person making the decision that day. Last week we were at Epcot at 8:45, it was a pretty light crowd waiting at the bagcheck/ticket/scan area, the gate person at our gate started letting us in, and then someone on the other side came and said "stop, not yet". She waited for 5 minutes then said ok. We still had time to get through the gate and over to the rope near space ship Earth. The guy running the show that morning was quite entertaining, had the whole crowd chanting and cheering. Then a couple of minutes before 9 am, the bus with characters rolled up, waved to us and danced a little, then got back on the bus. We did a count down and they dropped the rope, then we followed the groups of cast members from the ride we wanted to go on first (there were cms for test track, Soarin' and Mission Space, we chose soarin) as we walked to the ride. It was really cute, and a nice way to start the day, of course it really helped that the crowd was very small so there was no pushing or shoving.