The mysterious caller tells Gretchen to meet her at the racetrack at dawn. Yet in the very next scene when Gretchen arrives at the racetrack at presumably the appointed hour, it is clearly mid-day as indicated by the bright sunlight and shadows directly underneath Gretchen and her car.
When Gretchen and her mom, with Ricky following on his motorcycle, leave their house and head off to the prom, it is still mid-afternoon as indicated by the level of sunlight and shadows. Yet when they arrive at the prom at the high school, which isn't very far away from where Gretchen lives, it is already completely dark out.