The principal change so far is that I have mounted one of our outside cameras just in front of Box1 giving us a rather better external picture of what's going on there. We already have a great tit pair interested - they spent most of the day going in and out of the nest box. On several occasions, one of the pair stayed inside the nest box for over 20 minutes. Finally, we could see, even without an internal camera, that a great tit was roosting inside the box overnight. More detail later!
Unfortunately, because of a camera fault, we cannot show you any inside shots at the moment but I hope to have a replacement well before any serious nesting activity takes place. At least it has happened now rather than in the middle of the nesting season!