It has to be later than 9:30. First of all, it takes longer than 15 minutes for all the corrals to clear. And second, I know several people who had finish times right at 4 hours for multiple DLR races, and they weren't starting from the A corral. Maybe most streets would be open by 9:30, but the end part of the course that's on property has to still be open at 9:30.