I truly believe there are night people and morning people. It is just how we are wired. I've always been a night person. Even in grad school, I could still pull a few all-nighters in a row and in fact that's when I did my best work.
During much of my working life, we had flex scheduling. Some (many) came in to work at 6:00 AM. I came in about 7:30 AM (and didn't even like that) but stayed later. When left to my own devices (ie: not having to go to work in the morning such as during vacations) I can easily stay up until 3:00 AM and sleep in until the stock market opens at 9:30 AM (did I mention I am an active investor).
Anyway, I do post on HW late, but I rarely see other posts after 10:30 PM.
If you are a night person, feel free to post -- you won't wake me!