Professors are an ambiguous form of staff members, being that their schedule is more complex than unambiguous staff members. Professors may have a select schedule, but these are hard limits for when they are allowed to arrive and when they are required to leave. Professors will follow their own schedule based on the courses they are assigned to, so they will arrive anywhere from a few hours to right when a course starts, and remain there until their last course ends, or if they are able to, remain for a brief period of time for planning.