I can't imagine it starting ealier than 7, and probably more like 8, and then you have 30 minutes of opening act before U2 take the stage. If U2 were to start playing at 7:30, they'd probably be done at 9:30-10, PACIFIC TIME, which means on the East Coast of The United States, you're looking at 1AM, ABSOLUTE EARLIEST, probably more like 2AM.