Oak tree nestbox update

Well, the blue tits are still furiously collecting moss and the nestbox is filling up. I discovered where they are getting it all from. I went up the garden today to find that my hens (who I have been letting out in the top part of my garden) have been scratching up my lawn in places, where there is loads of moss. This has dislodged it and I presume the blue tits have been making the most of it. There were a few bits of grass bought in today and lots of re-arranging going on. They must have nearly finished?…..