Yes, birds have a "teenage" feathering If they are white with no other colors, they could be white adults. They will likely have other colors though if they are mixes. I believe a red sexlink is a RIW and a RIR cross. True colors will show at about 3 months when their adult feathers come in full blast.
Thank you! I was worried they would be all white & somehow white chickens remind me of the Far Side cartoon of a deer with a bullseye on his side... The other deer says "Bummer of a birthmark, Bob"
White chickens <-- cute, but hardly good "camo" to help hide from hawks in the field....
KK, then my Golden Laced Crested Polish is an oddball. She doesn't have the typical marking of a Golden Laced. She's all Golden with some black on the end of the tail feathers but the new feathers coming in on her crest are completely white. She is 3months and 11 days old. Here is a somewhat recent picture of her but you can barely see the white. I would say at least half of her head is now completly white.