I killed my deer this year at:

Doe Oct. 17th 5:15 p.m. Bow
6 pt Nov. 18th 5:15 p.m. Bow
9 pt Nov. 19th 4:15 p.m. Bow
Doe Nov. 25th 1:00 p.m. Bow
8 pt Dec. 1 st 10:35 a.m. Bow
Doe Dec. 26th 9:35 a.m. Shotgun

I have killed as many bucks in the morning as I have in the afternoons but I much prefer to hunt afternoons because I enjoy my sleep, but it's a hard to beat a morning rut hunt(daylight until noon) in terms of productivity. So my answer to your question is hunt anytime you can get in the woods, you never know when the time will come. One of my favorite hunting buddies and myself have a saying that we often use when we're hunting fowl conditions or we have sit the stand all day etc. That saying is "Must Be Present To Win"