Not been able to make any progress with this one.
Attracted to mix of MV and actinic light.
21/vi - 32
No interactions present.
Its been retained for chopping anyway.
My first thought was Argyresthia, but the antennae are too long for that genus, and I can't think of a better match than Caloptilia. Although I'm now beginning to have second thoughts due to the small size (I assume those are millimetre divisions?).
Entomologist and biological recorder
I'd looked at the Gracillariidae but not found anything the matched. Does look a bit worn though so may lack the key features.
Rachel Terry has now dissected this and identified it as C. syringella as you thought. Do you want to add the ID yourself as you thought it could be this.
Lat/Lng: 51.255, -0.3104
OS grid ref: TQ180520