Hmm... interesting questions.
I'm not the best person to offer advice since I'm in VA, but I'm guessing that if the eggs are in the coop with the chickens, their combined body heat would be enough to keep the eggs from freezing.
You can still eat them if tey are frozen though, as long as the shells aren't cracked, and you eat them the same day.
Are your layers a dual purpose breed? A laying breed may not be worth the effort.
I haven't ate any of my layers yet, but if I was going to, I would definately "moist" cook them. We have raised some broilers just a few weeks past prime (supposed to butcher at 8 weeks, we weren't able until 12 weeks) that were a little tough when roasted. So for me, anything over 3 months is going in the stew pot.