Jeez...i have the same problem now too. Changed my AP booking to avoid CA transit in PVG. When i called TK for seat selection, they cant do it and has something to do with AP system and their system not 'in synch'. And theres some sort of technical issue.
Called AP and said will reissue new eticket but still waiting for email......will have to call again when they open...
God forbids i get stranded somewhere as carrier wouldnt recognize valid ticket