I had another egg today with the rubbery yolk, I don't know if its from the same hen or not. When the eggs are frozen hard enough to crack I just leave them on the counter to feed to the dogs,cats,chickens the next day. Its not every frozen eggs either, just been the 2 so far. I know if you freeze eggs to keep for later use, you have to mix sugar, salt, or honey with them before you freeze them, I wonder if thats just what happens if you don't mix something with them before you freeze them?
Also a note on the frozen eggs, if they freeze hard enough to crack, it is not recomended you use them for eating because of bactria getting in. If you let them thaw, the crack will close up enough that you really can't see it, but it would still not be safe to eat. Feed them back to the chickens, or your dogs and cats. I must admit that I have used the ones that are just lightly cracked when I wasn't getting many eggs, and I guess I'm not dead yet.