They will last a long time in the freezer Clint, I have done some 4 or 5 years old and have some now 2 or 3 and never seen a difference. I have been turning all but the very best ones away this year just because of room. I hate doing that but you can only work up so many and almost no one wants to keep them unless they plan on mounting the head. I need to get started on some of mine , this is the best time of the year for tanning, at least it is for me. Cold and dry.
Pappy