I saw a few of these in late May to early June here, quite far north. They were lively, bright and un- or low-worn. They looked so fresh I was convinced they were emergents. Everyone told me it was impossible. We had no snow, very few frosts and a very mild winter.
Distribution is a bit surprising (none in Greenland though) the two for Svalbard are 7 July 1978 The earliest dates each year, combined with winter climate and known mass migration for the same year, may provide some evidence of spring emergents
The earliest GBIF ORKNEY record seems to be 3 May 1997
My picture is of a June 2019 specimen
The earliest for this block is 20 April 2002 (Scotland west coast)