We were there just about the same weekend this past year. Keep in mind that HS regularly opens before the posted opening time -- we got there about 8:20, were 4th or 5th in line, and they opened the gates at 8:45. We walked to TSM, got an FP for about 9:45, got in the standby line and rode, got out about 9:20, did Great Movie Ride, got back to TSM, our window had opened, got another pair of FPs for around 1, rode again (we decided not to use the 1 pm FPs and gave them away). I think this was on the Monday a week after Memorial Day. So not nearly as bad as you might think it would be, if you can be in line well before the posted opening time.