The Delaware in front, with the redder comb showing that her hormones are flowing, looks close to laying, the next one, with a paler comb, could take a while longer. The others I don't see enough of the combs to tell. Sometimes when it gets to late fall and the days are short, a pullet will delay starting till the days get longer. I think that is what happened with yours. And the days are getting noticeably longer now.