I took a picture in March once in Michigan of some monster bucks bedded by a road; I think if there are does in heat around; the antlers stay on- but that is a guess only.
I see muledeer out here drop their antlers by the first of December; especially if they are small bucks; fork horns- but I did see a forkhorn mulie on the 24th with both antlers.
The bigger bucks seem to hold on to their antlers a little longer- at least when I see bucks in the late hunt in December if a buck has an antler- its a 3 or 4 year old looking buck- and I see a lot of one antlered 4 by nothings and 3 by nothings. At the same time I see big mature mulies with both antlers.... and find equally big drops on the snow..
Not at all sure their is a scientific answer known- but I bet its seated in whether or not their are hot does around.
I saw a guy dress out a fat doe in September near McCall Idaho some years back- it was a whitetail; and had a half formed fawn in it. So that doe had to have come in real late.
I bet the buck that did the job had antlers to show off at the time
Here in the spring; airplanes fly over the ridges and drop paper markers with sand in them on antlers they spot. Then they radio down to their buddies on the ground.. I try to shed hunt before the planes show up