If I were doing this, I would get an Axanthic het for Pied female instead. In both possible pairings the theoretical odds of Axanthic Pied is 25% of the clutch. In Pied het axanthic x Pied het axanthic the remaining 75% of the clutch will be Pied possible het for axanthic. In Pied het axanthic x het pied axanthic the remaining 75% will have known genetics. The pieds will be het axanthic, the axanthics will be het pied and everyone else will be double het.