I don’t know that they’re duplicates, but I suspect. No knowledge on that one.
A while back someone in Australia was looking for the variegated type and mentioned the cultivar name, but I can’t remember it. It may have been a conversation on Permies? Not sure.
Not sure. I only found mention of one current breeder, and it’s very much a niche product, unlike carrots, so with as few seeds as the plants naturally produce even under ideal conditions, I can’t see why they would introduce cms.