Tradtusker, My *general* experience - searchin' for the *big* sheds - has been that the biggest mulies generally drop by the end of January and the biggest bulls drop by the middle of March (end of next week). The reason for this is because there is a certain amount of time required to grow a new set of *big* antlers for the next fall. I have seen smaller bucks and bulls with headgear clear into the end of June....
Of course, regional conditions, habitat, quality of feed, and other environmental factors may cause significant shifts in the time frame I have supplied. Most of my shed hunting has been in Oregon, Idaho, and Montana...although, I did hunt sheds successfully in Colorado back in the early 90's...they are definitely out there!
A local with a specific answer for the question that you have requested would be "golden" knowledge....
Good luck and beware - shed hunting can be addictive - I have been wrestlin' with it since I picked up my first shed in 1981....
Shoot straight, Shinken