As nice as only paying the HK price would be, I'm probably going to "split" the trip (since praying for a HKG-LON UC redemption to hold for long enough for the LON-NYC leg to open up? Seems like a fools' errand, even if there's plenty of HKG-LON-NYC availability) and buy the VS points I need to make it happen (because it's a $12,000 ticket from what I can tell; getting that for about $2000 [$1500 in bought points plus at most $500 in fees and APD] strikes me as a good use of points, and it preserves my Hyatt points for the SQ legs of this trip).