They are close, but my RIR's comb had a growth spurt right before she laid any eggs. So much so, I was wondering if I had guessed wrong and she was a roo! LOL! It was sudden...one day she looked like yours, a little red, small comb, then the next, she had a big floppy comb and started laying!
Mine got a growth spurt too. All of a sudden one day she had a BIG comb and started sqawking the egg song. I'd guess a few more weeks too. Their combs probably will grow a little more before they lay.
You keep them inside in the rain? Or do they just stay in there? That's funny. I agree with everyone, a week or 3 yet...I'd forgotten how lovely RIR are...Haven't had them in 10 years.