Originally Posted by
mahasamatman
You can only book complete awards from source to destination as the United search engine provides. You can no longer manually assemble an award with available segments. So, just because AAA-XXX and XXX-BBB are both available doesn't mean you can book the award unless the search engine returns AAA-XXX-BBB as a valid option. It's been this way for a year or two now.
Correct; and, I agree, that's likely what the problem is.
If a schedule change occurred (or occurs), you can probably get UA to move the connecting flight to the night before. Otherwise, yes, I suspect this will now price as two awards.