I agree, those are cockerels.
Hatcheries usually say that sexing is 90% accurate somewhere in the small print (less accurate for some breeds, usually noted in the breed description). They often will give you a refund if you end up with more than 10% males.
I'm a new chicken owner, I ordered female chicks from a hatchery. White Breese and Speckled Sussex. They'll be 17 weeks in a few days, I'm starting to suspect that a few might actually be males but I don't know!
Hatcheries usually say that sexing is 90% accurate somewhere in the small print (less accurate for some breeds, usually noted in the breed description). They often will give you a refund if you end up with more than 10% males.