Bumped into this myself when I first got to Solution Nine while doing MSQ. I happened to clip against it I guess and got shot into the air and stuck there until I moved just right and fell back to the ground. I thought it was a one-off thing until someone in my FC brought it up and gave the coordinates. Sure enough, hopping against the invisible wall at 11.3, 13.9 (just off the aether plaza) pushes you further and further into the air until you happen to pivot or step just so that you fall back to the floor. This time I had to teleport to get down.