Had a USDM booking to Europe return in J for two, problem was only flights out of HKG were via NRT had to say 2 nights and go on JAL 787 with not so good J seats reviews to CDG, looked and looked over few weeks to change HKG direct CDG (our stopover point), made a few calls all to no avail. Eventually (or lucky) last Thursday found a flight a day earlier, CX direct to CDG on BA and Award Nexus, called up and bingo had it changed, so saved 3 days in all, OK cost USD$150 each but we feel it was well worth it getting 3 extra days on the ground in Europe. So the motto of this is don't give up, try and try again if need be.