Thanks for sticking with this one! Last update changed the skill's numbers, but actually casting it still used the old 4/8/12-second timer. That's fixed and live now: Nimble Feet lasts 200/400/600 seconds at levels 1/2/3 on every job. Cast it anywhere - the buff icon should start near 600s at level 3, and the skill tooltip says 600 sec. (Refresh the game if you still see the old timer.)