I go in about 30 minutes before shooting light. I was kind of thought it doesn't matter if you spook a deer an hour before daylight or 10 minutes before daylight. They are either going to book it out of the area or circle back around. So if I spook one an hour before daylight and he circles back around I am not going to see him and if I do I likely can't shoot. If I spook one 10 minutes before daylight I he circles back around I might be able to do something about that before he leaves the area.
There is nothing quite like sitting in total darkness and hearing something busting toward you in the dry leaves and you have no idea what it is.