Curious if anyone has thoughts on this - traveling HKG-KIX. Booked an Economy Essential fare. W=0 at booking and has remained 0 but open seats on the seat map. Wait listed mileage upgrade for PE, which did not clear in advance. At Cathay check-in, W still shows 0 but I ask about mileage upgrade, agent makes a call and in less than 30 seconds, says no problem and uses my points to upgrade. Any idea why Cathay may have been blocking W in advance/even hours before flight with open? Only thought was a potential plane swap or forecasted IRROPS…