Originally Posted by jsloan

You’ve gotten lucky. What you describe is expressly prohibited by UA’s contract of carriage, meaning that there are no legitimate reasons to do it (as far as UA’s concerned). They don’t want you reserving space on two planes and only taking one. They want you paying sky-high last minute fares.

There are many, many reports on the forum of people who have gotten a phone call from UA asking which one to cancel — or of people who have had conflicting itineraries cancelled outright. There are even some reports of UA shutting down MileagePlus accounts for making a lot of unneeded reservations and then cancelling them at the last minute.

To the OP: While you can certainly try pricing out IAH-SFO-BDL, in most cases that’s going to be extremely expensive. Instead, just cancel the IAH-BDL segment; there’s no charge for cancelling. Then, book IAH-SFO.