Article and note supporting main upset for art lover (8)
I believe the answer is:
aesthete
'art lover' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
(Other definitions for aesthete that I've seen before include "person of culture" , "Poetry lover maybe" , "Someone claiming special knowledge of beauty" , "Lover of art and beauty" , "Person who appreciates the beautiful" .)