I believe that IN GENERAL the big hatcheries are trying to sell egg layers that lay well and do not particularly concern themselves with the APA SOP. Obviously that depends on the breed, some will not be good layers year after year no matter what. Cubalayas for example are more of a Yard Art bird than a layer.
I would GUESS that among the small breeders there would be a range between "breed in hopes of getting a greater quantity of show bird quality birds not concerned with egg quantities nor # of laying years" and "my breeders meet the spec, breed true, are decent looking and now I would like to increase the egg laying capability". Just how you find the latter type is probably difficult but both the Ameraucana Breeders Club (
http://www.ameraucana.org/ ) and Ameraucana Alliance (
http://ameraucanaalliance.org/ ) have lists of breeders in their clubs. When it comes time to replace your BW Ameraucana, you might check with the breeders and see if any do have an emphasis on SOP and egg laying ability.