This morning I put the nest box fronts back in and put a nest bowl in the boxes. The cocks all seemed keen. I am hoping to pair up tomorrow. The funny thing is that I have 2 Dark Chequer two year old cocks who had their own nest boxes last year. During the winter while the fronts were out these 2 cocks were quite happy sitting in the box perches instead of their boxes. 2 yearling cocks had taken their boxes. But as soon as I put the fronts back in they both took their boxes from last year back. 

Before putting the fronts in. 

With fronts back in. 

Video clip of the cocks.