I have always been a morning person. I wake up instantly and regularly at about 5:00 am, and my body is ready to go. My preference, given sufficient warmth, is to ride in the early am - I even do 20-30 miles without breakfast before 7 am in the summer time. Or sometimes I will go out for a ride and have breakfast along the way.
My body says "nap time" around 1:00 pm or so.
However, I ride whenever I can,
Today, I rode about 2:30 pm (after my nap, of course!), as it hadn't warmed up much before then and I had chores to do.
At 2:30, the temp was up to 55F, and I had a great 20 mile ride.
I think it is hard to generalize about what "everybody's" bodies are like. We are all so different!