We have one non-055 itinerary that's still very much alive, COW8C fare with no AZ metal, purchased directly from the issuing carrier's website. We need to change the date of the last two segments, and are deliberating how to accomplish this --- i.e. wait until enroute and deal with the non-SkyTeam operating carrier of the last two segments in question, or contact the issuing carrier before starting the trip (especially if they intend to not honor the tickets at all, much less permit a date change). Advise (hopefully without snark) would be appreciated!