To also answer one of your original questions, to my knowledge, people who have bought a later Zephyr, the trailing edge was not wearing as fast as the earlier batches.
Like everyone has said, its not a UL, but rather I personally consider it a Light Standard. However, Mark Reed has posted in the Prism Forums that removing the upper spreader and moving the bridle setting up against the light wind knot, or perhaps past it, can be done to help the kite in much lighter winds.
I did happen to find this vid a while back, you can see the upper spreader missing, doing a fade and a turtle in a supposed 0mph with the Zephyr, with footwork of course.