Arthur's been talking about moving up for some time, really struggles to make weight. Suppose the guy at 135 with the WBO vacates, Arthur will have automatic high ranking at new weight being champion at the other weight, coupled with Khan's high ranking and there's your roundabout (Frank warren stamped of approval) way to a world title. Seeing as the main players at super feather are leaving or retiring, Arthur may make the move up earlier, he's been looking for a big name opponent.