Which is why I am sitting on hold at United Airlines, and thinking, once again, why I never, ever, ever fly anything but JetBlue or Southwest Airlines. I'll update this after I get to talk to a person, but I just want to point out that when JetBlue did a flight/equipment change, they retained our purchased seat upgrade.
Oh, and their automated system wants you to pronounce the last name of the flier(s), which is stupid, because they think names are phonetic or something and they make you try twice before giving you the option to spell, which is where I always start with this last name.
ETA: They did the seat upgrade replacements over the phone, but you have to watch them or they'll stick you in a limited recline if you aren't really on top of things. They guy was really nice and the policy is not to charge even if there is a price difference. If I actually get the e-mailed update, I will grudgingly concede that they at least did make it right, but I still think they should have gotten it right automagically (like JetBlue) and I should not have had to catch the limited recline issue.