That is what I thought until I got some BR's and they look nothing alike. Maybe the new ones are just better quality??? Here is 2 of them and they are 2 weeks younger but have never resembled the others.
Flash is a Barred Rock pullet. Loki....I'm not really sure on breed, but not Barred Rock. The other 2 Barred Rocks you got are cockerels which is why they look different than flash. Here is a picture of my pair. The roosters always have more white on them.
She's a pullet for sure, but still no idea what she is. could be a production black, that's as good a name as any for a barred based bird from a hatchery. In all likelihood she's an Oops bird.