if you're going to keep bringing the 777 and "landing/drag flap" into this.
Flaps 30, 25 and Flap 20 are all valid landing flap settings on the 777, though F20 is reserved for some non-normal situations (usually but not exclusively if performance is an issue, e.g single engine landing). PB thought out of the box and swopped one valid landing flap setting for another one, albeit at very low level.....