Sometimes bucks will drop their antlers early due to injury or severe stress of some kind
I believe this 100%. Having had the opportunity to work with several outfitters over the past few years, I've seen evidence first hand of bucks dropping one or both antlers very early after a devestating fight or a very bad injury such as a non fatal gun shot wound. I'm no biologist, but I believe the reasoning for this is to stop being challenged by other bucks still participating in rutting activity. Avoiding conflicts would be very beneficial in recouping from the injury. Jmo.