I'm assuming these STBY periods are assigned to you while on reserve. What if, instead of a STBY you were assigned a 13 1/2 duty hour trip on a 1 hour call out? If you are on reserve and you know the possibility exists that you may be called for a trip, isn't it your responsibility to be rested and prepared? A lot of people seem to treat reserve peroids as their own time and a trip assignment as an interference. It may be hard to do, but if you have reserve starting at midnight, you need to be resting during the day...not mowing the lawn, hitting the gym, buying groceries, etc.