I signed a non-breeding contract too, and I fully plan on getting Chinook neutered, but when my vet and I discussed it, he recommends waiting until 1 or 1.5 even, so he is fully developed. (testosterone is impt.) Chinook's breeder so far has left us alone. I told her I would send her a copy when it is done.
Chinook only has one that has dropped, and it too is the size of a small marble!