1AM is extreme. I wouldn't even call that waking up early, more like just staying up all night. When I was in high school I worked 10PM to 7AM, and that was terrible. But, I was able to, at a young age learn exactly how much sleep I need and what it took for me to sleep (pitch black darkness - eye mask).

Now, I consider 5-6AM early and that's when I typically wake up - haven't used an alarm in years.