Absolutely, I used to stay up until 4 or 5 AM all the time. I did have the advantage of never being a late sleeper. If I fell asleep around 4, I would be up no

Absolutely, I used to stay up until 4 or 5 AM all the time. I did have the advantage of never being a late sleeper. If I fell asleep around 4, I would be up no later than 9 on average. The way to transition is to pick time for bed, and for waking up. It will probably suck at first. You'll have a hard time falling asleep and/or a hard time waking up. If you wake up consistently at the same time your body will adjust.