Originally Posted by xliioper

The fault is entirely on the side of DL. KL systems clearly know and recognize their own W/S/A fares to be Premium Economy fares. DL's booking and seating selection systems also recognize them since it books you into PS seats on DL flights. It's only DL's Skymiles crediting system that is still treating KL W/S/A fare classes as Economy classes that KL had previously used them for before introducing PE cabins and fares.