I think they are BSLs. You can't see it in the photos but they have bright red feathers on their chest and necks and are exactly the same size and body shape as the RSLs. Also, the person we bought them off said the father was the same.
you may be right... I do have a BSL that is almost entirely black. However, she was labeled at TSC as a Hoover Black, which I’m now wondering is a production black? Or if a production black is the same as a BSL? This is a pic of her, my girl Midnight.