Dear Charles & Jamie
Having reviewed the original image I'm inclined to agree with S.
fonscolombii on this specimen, as the veins do look red. For your records it
was just off the cliffpath at the end of the BBC field. The small panels at
the wingtips (pterostigmae?) are mostly pale with dark veins to the fore,
which I think may further confirm the identification.
Many thanks
Andy