There is no possible legal way to ban commuting. It's too hard to legally define...

If they require all pilots to be in domicile 8 hours prior, then that is duty and you get paid for it (and it counts against your other duty limits).

If they actually banned commuting, they would lose 30% of the pilot force...this career is not worth dragging your family all over the map for, may as well go back on active duty.