I fly a schedule where I leave home at 2130 and return around 0530, depending on weather and courier. With this schedule, I am definitely not a morning person, but generally get up around 1400 so I can get a few things done that must be done between the normal 8 and 5.
It took about a month to completely adjust to the schedule and figure out a routine to help with my problem times of Saturday morning and Monday evenings. I take a nap for a few hours on Saturday and go to bed early that night and try and force myself to sleep until about noon on Monday to help adjust to "vampire mode" for Monday night.