For the past wee, there's been a Blue Tit checking out the box quite frequently on a daily basis. I hope they decide to nest.
I also have a box on my apple tree but it only seems to be sparrows who are interested.
It was nice to see the male swallow that nests in an outbuilding show up for the first time since departing with his mate and 2 broods last Autumn, it will be a week or so before the female shows , if she's made it.