I've no reason to doubt Mr. B either, Robbo. I just thought Wrenny might appreciate some more detailed information.
Wrenny, sorry it's taken me such a long time to get back to you. Vogelwarte wrote to me twice and both messages ended up, for some, strange reason, in SPAM.
I'd hoped that they would come back with some explanation of movements; if I recall, there's a ton of sightings each (early) Spring, then far fewer, and then another wave in the (otherwise quiet for a lot of birdwatchers here) summer. No news on that, but some interesting links (one only in German, I'm afraid), and news of a sighting of three (3) at Giswil (OW) on July 24th. That's only 24km away, due south-south-east.
The general feedback? Very possible; especially in the western Alps.
All the best -
In reply to Dave - CH:
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