I naturally go to sleep about 3am and wake up 9am. I tried different hours, but it was unsustainable. I would feel terrible the whole day as it is just to possible for me to fall asleep let's say at 11pm or even 1am. This was a horror for me and actually prompted to start my own business so I could be in charge of when I work. I was only able to find one employer before that, who was happy for me to come to work at 10 or 11. Different employers after a period of time would report that other staff feel that I am getting privileges and they also would want to come "when they please". So that would end up with me quitting. It's a shame that somehow 9-5 is embedded in our culture so strongly if you want to oppose it you are being viewed as if you were saying a blasphemy!