I am considering renting from Enterprise at an off airport location starting on a Thursday afternoon and returning on a Sunday afternoon. The location is closed Sundays but allows for after hours returns. If I were to delay my rental return by three hours (e.g. return on Sunday at 7 pm instead of 4 pm) would they know it?

I was wondering whether drop box key returns were time stamped or the GPS locating device possibly embedded on the vehicle were checked.