I am interested in this also for this reason... Say I breed Het x Het one year and am lucky enough to get a visual male. The following year I breed him back to mom and have a viable clutch. If there is the possibility of a 13 month sperm retention how would I know if the normal looking offspring are 100% Hets or 66%'ers. Is this a concern anyone else has? I would hate to sell something as 100% and not have it prove out.