You cross extended black barred male with a duckwing (wild type) female the offspring are barred extended black/wild type females and single gene barred extended black/wild type males. You cross those together and you get 25% extended black/extended black, 50% extended black/wild type. And 25% wild type/wild type.Not what I've read in the past, but okay .
I'm liking the new emojis.
You'll get half barred females and half non barred females. Half single gene barred and half double gene barred males. You hatch enough you'll get wild type/wild type females with barring and wild type/wild type double gene barred males.
Those are your creles and they'll breed true together.