Backstory: I am a 26 year old male who works in the emergency services doing 10-12 hour BLS medical transports. My typical shifts start at 5 am but I have to be awake at 4 am to eat a quick breakfast, slam a cup of coffee, and commute into work. When I first started I use to be able to go to sleep as late as 11:30 pm and wake feeling sorta refreshed. However, after 2 years of this, I am starting to get worn down by the early waking routine.

Problem: I have recently been trying to go to sleep before 9 pm the night-before in order to get adequate sleep - I end up rolling around and staying completely awake until around 11:30 anyways.

Question: Is there any way to get into a proper 4 am wake sleep schedule or is that just too early for the circadian rhythms to sink? I am thinking about starting to take a nootropic sleep stack in order to assist with me falling asleep this early. Any other tips or helpful hints you guys can provide for extremely early wake cycles. I think it'd be pretty badass to feel super refreshed waking up at 4 am and being able to work a full work day not feeling that disgusting and headache inducing exhaustion. I really hate the feeling. It's like being spun out on amphetamines.