Swallows back in the barn!

It's been about six or seven years since we had Swalloows nesting in the barn. The first year they did not reappear to nest on site was a very bad year for Swallows due mostly to weather and we saw no signs of them down on our land. The last couple of years has been better in that we have seen them hawking sometimes over the fields but this year they seem to have gone one step further and they are currently occupying an articiial nest I put up nearly ten years ago that has been unused by Swallows up to now. No photos as I don't want to disturb them yet.