On work nights, I try not to stay up any later than 9:30 PM. If I'm not working, I may end up staying awake til after 11. Lately though I've been going to bed after midnight... I need to stop doing that. I like sleep.
Between 11-12 pm usually. I had insomnia in the past but I improved my sleep pattern a lot with help of weighted blanket therapy, you could look here . These weighted blankets are really useful stuff. Now I can sleep 8-10 hours per day.