Overall quality of eggs seems bad.

[aart]

https://www.backyardchickens.com/threads/fermented-feeds-anyone-using-them.645057/

Old feed is not necessarily funky by sight or smell...
......just that the nutrition can start to degrade/decrease.

2 years can be the start of 'old' for high production hybrids...others not so much.
Some birds just have funky plumbing, I have had a few that consistently had blood/meat spots.

 

[lazy gardener]

We've had more weird eggs as the heat has gone up - definitely more soft shelled eggs. I make them tubs of ice with chunks of veggies or fruits in them, and was going to make them some electrolyte water today. I just threw out the bags, so I don't know how fresh it is, but it didn't smell moldy or anything so I didn't check the bag that close. I wondered about the "extras" if that might throw stuff off.

Honestly though, these hens have always had weird eggs off and on, ALWAYS with the meat spots - out of 7 eggs, 5 or more have them - which I figured went along with their systems maturing. We've had eggs with NO shell, not even soft, just yolk and white, under the roosts when they were real new to laying. Slab sided eggs, soft shells, you name it. Chalked it up to working the kinks out of their systems. The heat has seemed to increase all matter of weirdness for them. They are super happy ladies though.

What are the breeds of your girls, how old are they? I'm guessing that your girls are from inferior stock.