RE: how early is to early
I hunt mostly public land, and I can say that if you get out there at 4am you will probably not be too early. LOL
Around here if someone knows your vehicle, and you are considered a good hunter they will park right next to you and try to find you in the woods. It's insane.
Like the others, I would recommend getting farther in the woods and let the other hunters push the deer to you.