A lot depends on what type of air driving. PT air driving or air exception air driving. If you mean PT air driving where you have a regular start time and or route then that job comes first and any other delivery or pick ups would have to work around that. Air exception air is extra work and you are still responsible for your normal job. During peak (unless you are a complete looser) all your bosses want you to help them first. You may mean being a peak seasonal driver then all you will do is deliver if there are enough trucks to drive then you will be a driver helper.