Learn something new every day.
I've never seen a blue egg from a hatchery bird.
EEs are usually mixed with either Araucanas or Ameraucanas. The color of the egg usually depends on what breed or breeds they used. I get some pink eggs, so the other breed nust have been a light brown or white layer.
I've tried to find the same breed I had years ago, like 30!
I used to be able to spell it the way it was spelled then, but I can't figure it out. LOL
The name was closer to Ameraucana, but they didn't lay plain blue eggs. They were swirled and rainbowed. I had a few hens that laid swirls of purple and gold and blue. Others were blue and green, blue and gold, just pretty eggs like the one you color for Easter.
I wanted chickens again only for that breed and have yet to find them except from a guy I used to live near in the Bay Area. He kept them under lock and key. Never sold them or hatching eggs and I begged for them. He'd bring eggs into my job to tease me with them. First time he brought them I shocked him when I said what they were and we must have talked chickens for hours.
I haven't seen him in 15 years. Just realized that, but man if I could find him and he still had them, I would too. Some how some way. I've asked around on this forum and someone directed me to a person here just before my husband died and now I have no idea who he was, but man do I want those birds again. And they were South American birds.