Over the past few days I have noticed swifts flying close up towards peoples' houses in the area of the colony on Mill Road and briefly hovering but not entering any holes.  I have found out (from here: http://www.sos.org.uk/recent-sightings/view-2952.html) that this is possibly young swifts not quite ready for breeding this year but searching for likely looking nest sites for following years. 

Mike Beard