Looks like I have some back peddling to do. I posted I had 2 BCM hens that started laying. After over a week I can say with confidence it’s just one. 
We found two Marans eggs the first day. After that we’ve only had one dark egg a day or none. Those two eggs were also suspiciously similar in size, shape, color, and speckling. There could be a few things going on but I’m guessing we missed an egg. Then collected two the next day. Because we were not checking regularly yet. Oops.

We found two Marans eggs the first day. After that we’ve only had one dark egg a day or none. Those two eggs were also suspiciously similar in size, shape, color, and speckling. There could be a few things going on but I’m guessing we missed an egg. Then collected two the next day. Because we were not checking regularly yet. Oops.