Species account from Moths of Glamorgan
(Gilmore, Slade & Stewart, 2009):

Univoltine, flying in June and July. Known only from a late nineteenth century record until it was rediscovered in the north-west of the county in June 1999. It remains a very scarce moth in Glamorgan but as with other upland species could quite possibly be under-recorded. The larvae feed on Bilberry as its common name suggests, though usually where this grows under woodland cover.