Originally Posted by
corporate-wage-slave
The GUF should not make any differences since it is further back in the process. Avios may sometimes be a factor but if you are ticketed then usually that is OK. There are many such queries with USA destinations, I suspect it's related to that, often it mysteriously works after a few hours. My guess is that it is a document check flag and can be resolved at check-in.
I’m starting to suspect there is an issue with the U.S. systems (possibly related to the Shutdown), as my couldn’t OLCI in DUB (for a DUB-LHR-DFW run) on the App, eventually allowed check-in for the DUB-LHR leg only via the web site, but still refused the LHR-DFW segment despite also being within the 24 hour window. At the counter in DUB later that day, they simply concluded it was a “check-in with AA” flag, possibly related to a documents check, despite having my U.S. passport there and scanned in…and having been submitted to AA a week before via their scan your passport system for passenger data.
Checked with AA the next morning at LHR, and they simply needed to scan my passport (already done online and at DUB) and cheerfully checked me in. Occurred 28 Oct, 2025.