I think close to 8-11 months? That is the age they are supposed to still be pretty tender, but I will let someone more experienced with processing answer that one for you...that is not my arena of knowledge
the bird in the center of your last picture looks like it may be a girl. Hard to tell from the pics, but the comb of that bird looks smaller, and less red than the others. Can you get a better pic of it?
well, we can give you a pretty good guess...if you want to post separate pics of each we could give it a go...but from what I have learned here on BYC, SLW males will have white "shields" on their shoulders as feathers come in, and their combs and wattles will be more red, and better developed...
I see a bunch of poor quality SLW as well....some single combs, poor lacing, but seem to be of the SLW ilk...what breed did you order? I see a red bird, and a barred bird in there.
I have read from another member on here that SLW roos will develop white "shields" on their shoulders...