With the OnePass number surviving as OnePass and MileagePlus accounts are merged this weekend, what happens if Chase, Reward Network/iDine, a hotel or rental car partner, etc., submit miles using your old MileagePlus number? Or, for that matter, if you have an existing reservation for after March 4th which uses the MileagePlus rather than United number? I'm trying to update everything which used my MileagePlus number to use the new Continental-style number, but I know something things are in process now which will post after March 4th, and I also am sure I'll probably forgot to update some partners. I assume for a period of time, the system will process both. However, I haven't been able to find the answer when I use the search on the United website.