Confidence: It might be this.
Notes: I think this could well be Hadena confusa (Marbled Coronet)as opposed to the less variable Hadena compta (Varied Coronet- seems like a contradiction). 'Marbled' appears to be much more variable than 'Varied'. Varied Coronet has a distinctive complete white cross band over the middle of both wings. This one hasnt got it but does have dull yellow markings where Varied has white markings, so I hope I am right in thinking this is probably Marbled Coronet.