As someone who used to be like that but now has a real fucked up sleep schedule due to unemployment, I can tell you the deciding factor is a consistent sleep period. The vast majority of my career has been waking up at 4am and going to sleep at 8 or 9pm. Thats easy to fall into and even when you’re off your body just knows when its time to sleep and when its time to get up. Ive gotten up on time a few times despite the alarms failing to go off for whatever reason. You want good sleep? Set wake up and bedtime. Your body will adjust.
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As someone who used to be like that but now has a real fucked up sleep schedule due to unemployment, I can tell you the deciding factor is a consistent sleep period. The vast majority of my career has been waking up at 4am and going to sleep at 8 or 9pm. Thats easy to fall into and even when your off your body just knows when its time to sleep and when its time to get up. Ive gotten up on time a few times despite the alarms failing to go off for whatever reason. You want good sleep? Set wake up and bedtime. Your body will adjust.