The problem is getting worse. This morning when I let them out of the coop I found a yoke with a soft rubber shell next to it. I tossed some extra oyster shell in the run today. Hopefully they eat some more of it. Also I'm not going to let them free range today to force them to eat only layer feed to see if that helps.
What they eat really doesn't seem to matter. I mean, the calcium is good, but if it's a glitch in their internal system it's just got to work itself out. It usually takes a few days, and new layers often lay weird eggs on and off the first few months. No yolks, double yolks, no shells, weird shells, things like that. It's all pretty normal and works itself out. You just never see those eggs for sale in the stores, so folks don't realize how common they are.
Came home from work today to another very soft floppy shelled egg. It wasn't broken yet but was like a jelly egg. That's two yesterday that had thin shells and two very soft or broken shells today. I hope it stops soon.
I was having a similar issue with my hens. I did some research on it and most answers said it was stress related. I assessed my coop/flock environment and did some rearranging in the coop of the roosts. There was always squabbling at night about who got the best spots between the pullets and the year olds. I made more "premium" seats and the squabbling stopped. Within a few days so did the weird eggs. They seem to be laying better iTake some time to watch your chickens at bedtime, during laying hours, feeding etc. look for signs of stress then address the issues. Good luck!
Whoops, cat hit send before I was finished! ;-) I was going to say that laying in general has improved and everyone seems more relaxed. Also look for changes in environment. New dog, new noises, etc. Hope this helps