Originally Posted by
1KHI
Do you mean 4 hours on domestic trips, right?
If you're taking next available flight, it should be no problem and offered by the system. Unlikely supervisor will override it any other way. You can try pricing it using multi stops itineary and check the difference in fare. You can also try to do a SDC on your departure day.
I just went on UA.com and found an IAD-DEN-SFO routing that gave me a 6.5 hour layover in DEN.