Same every year, they can shed starting in mid to late December through April for many reasons though the majority shed in March. I think Loneranger meant longer daylight affecting antler drop, another of many factors. I usually don't get serious looking until close to the spring equinox when the amount of daylight starts to lengthen to more than darkness. Seems, at least for me, I find more after that happens every year.
I know of a 190 class buck that shed around May 3rd one year, found it hard to believe myself but it's fact and I have the sheds. He shed after beans were planted on May 2nd and found when the beans were picked in early November.