This looks like 14 eggs to me. When will they stop?Two years ago when the same thing happened and we had two females laying in the same nest box we ended up with 20 or 21 eggs!
Here are the two females. My guess is that Suzie is in the nest cup and Rosie is above her in the picture. This is based on their head feathers and the white band around the back of their heads.
Another shot of the eggs. With two females looking after them the periods for which neither female is in the nest box are few and far between! However, I think there are 14 eggs here.
But where is the Box2 male?
Rosie and Suzie seem to have reached a working relationship. Although they still squabble a lot and compete to see who can get to sit directly on the eggs, but none of this looks serious and there are often periods of calm when they are sitting side by side.
I wonder whether there is any danger of the early eggs starting to develop too soon? We will be able to judge this when they start to hatch which should be about 12 days after incubation has started.
This picture was taken well after dark and shows that both females are now roosting in the nest box. Another sign that Rosie and Suzie have reached a working agreement!