If you can’t make the commute, you just call the company. They assign your trip to a reserve. If you can rejoin the trip then you get back on the trip and they charge you user time for the part that you missed. User time is basically sick time. If a line holder picks up your trip then you can’t rejoin the trip. If you call out with less than a 2 hour notice for your trip, then they could put a note on your schedule. Too many call outs and you will get called in to the chief pilot’s office.