Naturally I would do it whenever I felt like it, but sometimes things dont go the way you want it, depends!
I'm asleep before 9:30 PM every night.
I wake up at about 2:00 - 4:00 AM most mornings though.
I have scheduled timings with a window of flexibility. I just find it keeps me better disciplined this way.
I do what I want, but sometimes I purposely ignore them too.