Not all will have red patches, but they can come in at any point. I've seen most tend to start around 4-6 weeks with some showing earlier than others and some being really subtle late bloomers. Every bird is unique, especially in a mutt like these. Yes, I would say comb is generally a more...
It is gorgeous isn't it? The red on the wings is a bit oddly placed though and add that to the red on the back with seemingly rounded saddle (although still a bit young) with no clearly pointed hackles and somewhat small comb and I'm like meh...hard to know. Maybe late blooming cock?
I agree it looks like a cockerel. What's his mix, do you know? Looks to have a cushion comb from these pics so I'm guessing Ameraucana and rose comb rir? I'm bad with cross breed though