My Amberlinks are 5 weeks old tomorrow and they all have red in their combs. They were in Pullet bin from TSC. They can't all 6 be roo's. Do Amberlink hens have a red comb?
That isn't REALLY red, yet. I'm pretty sure amberlinks are sex linked so you should be fine. They look like pullets to my mostly uneducated eye, anyway.
When I first got chickens, I didn't know that hens grew combs too. Yeah, I know... NOW. But I didn't then. As my 8 little chicks grew, and they all began to get combs, I was freaked out that *I* was unlucky enough to get ALL roosters from the pullet selection - what was that 90% accuracy all about?!?!?!?!
Also, many breeds have very impressive combs, even the hens, such as Leghorns. And RIRs.