After a second Kamin day (the technicians never finished installing the stove on the first Kamin day, and despite a second day will have to come back again) during which there was much human movement in the garden, the bird did not come to visit for two days.
Now things seem to have gone back to normal, the Eurasian Tree Sparrow went back to its nest in the first box and birds paid the second box a number of visits. This morning the list of usual suspects has gone up from 1 (Blue Tit) to 3 bird species...
Here below snapshots recorded by the video server.
At 8:14:15 (at 1 second intervals):
At 8:15:19 (at 1 second intervals):