My Cuttings Froze!!!!

So we broke down our mothers and placed the cuttings in water in jars and buckets. When I went to start plugging in the morning I found that the water had some ice shards/sheets in it. I quickly changed them all over to room temp water. Some cuttings had black leaves and where obviously no longer usable. Most of them however seem to be doing ok, a little floppy and some leaves are curling a little . Has anyone else experienced this situation? What was your outcome? Its been about 3 days. If they where gonna die would they be dead already? Will they be stunted in the long run? These little girls are the majority of our upcoming year. Should I be looking for back ups? Thank you!!