Since it's a really long flight you want to make sure ... keep calling the 1-K Int'l Desk (maybe try the U.S. #, not HKK) until you get a firm answer (hopefully yes). It may only be a small price difference to "buy up" to the lowest SWU upgradeable fare. I've done it - bought a tix on the web, then decided I wanted to use my SWU, called in, forked over $125, and voila -- a fare I could use, plus secured seating in Business Class. Good luck!