If they are Bsl then a roo would be barred like a barred rock. You'll see a lot of people ask on here if they have a barred rock or bsl roo because they look so much alike.
Pullets usually grow in more straight tail feathers and faster also. Just generally though. Some breeds I'm not farmiliar with maybe be different in that area.
Same thing just a different names for different hatcheries. That is what makes them great though. As long as they hatch without a white spot on their head they are female, so the hatcheries can sex them easier and sell only pullets in the order. They are also fast maturing which is why they are...