If your area has a lot of pressure with groups pushing timber than sit all day. AM and PM sits you will see deer if land is getting pushed around you. Shotgun season is a lot like blind luck in pressured areas. You could kill a buck that has been pushed from over miles away. If you are in an area with not a lot of pressure I would sit both AM and PM. Seen some good rutting activity going on as of late. Sitting last night I saw a mature buck chase a doe pretty hard in open ag. Another thing to consider is corn in your area. If you have any corn fields still in GOODLUCK! Ha, Late corn could result in does coming into heat later since not being breed in Nov. In areas with standing crop does were able to get away from bucks easier. with crops coming out late could result in longer dragged out rut activity. I know it has been a question in the past but if you have standing corn in your area. 100% the deer are in it. They're not dumb!