We already explained this several times on the forum, it's not a bug, it's just that we chose to place the refueling point in the NGXu configuration that comes with GSX in it's REAL life position, since we'll eventually have a new kind of animation for the Hydrant crew that won't use the raising platform, but will use the big cable rocker and likely a stairstep to attach to airplanes with lower wings.
But of course, the whole point of having an airplane configuration editor, is that you can chose to bend realism a bit to your liking so, if you move the refueling point to a place that will result in a least 3.40 meters from ground ( which is the lowest the platform can go without having that guy's head bumping into the wing ), it will satisfy the rule for the Fuel Hydrant minimum height, under which the smaller truck will come. This way, you can get the Hydrant now, instead of waiting for the update.
