Hi! I'm kind of new to this chicken stuff. Last spring I bought tiny little peepers of different types and grew them big in a tub in my guest room. Built an 8x8 coop and an 8x8 run for them and when they started escaping and pooping in the guest room I put them outside. They grew and grew and finally started laying. At first every other egg was double yoked. Then they settled down and the double yoked egg is very rare now, nearly a year later. But about a month after they began laying, I got two GINORMOUS, HUMOUNGUS eggs...like yours. I, too, took photos of them, and I show them to everyone. They were HUGE. I still get the occasional jumbo egg, but most are regular sized now, some are large. I only have 7 hens. I still haven't figured out who lays which eggs. I generally get anywhere from 3 to 6 eggs per day, with the occasional gust of 7 eggs. Three or four are what the grocery store sells as "jumbo", most of the rest are large or regular, but the lighter colored ones are on the small side.
In other words, I have no idea what the answer is, but I'll take what I get. The giant eggs were kinda cool, though, and since I work with a guy who has a couple of hens, we often compare eggs. So far, I'm the winner. LOL