Originally Posted by
docbert
Odds are you won't be able to change it online - or at least not on the United website. You used to be able to, but they removed the ability a year or two back.
This had not been my experience at all having done this back in March. The key is to add the flight to your United account (I.e. you're not changing FF numbers your simply importing it to your Milage plus account)
-James