It seems there has been a complete "changing of the guard" at this nest site.
Apparently, in late March, it was decided that three large deadish pine trees, which Beau & Swift had been using for at least seven years as their favoured roost site, needed to be cut down, presumably due to their horizontal branches and lack of leaves.
On April 2nd, two days after the pine trees were felled, Beau was seen for the last time. Four days later another male appeared, which the Recovery Project is calling "Streak," as he has a clear black streak on the left side of his neck.
Swift had been observed accepting the new male & sleeping in the nest box until April 9th or 10th, when a new female appeared. Since then, Swift has not been observed in the nest box, although she has been seen in the area. The Project is calling the new female "Diamond," as she has a diamond shaped pattern of spots on the left side of her chest.
Very sad to hear that Beau & Swift have been usurped.