I have heard of this problem before, and a variant involving starting in Dublin, going to London and continuing on AA. It's to do with SABRE being disconnected from Amadeus, and AS refusing check-in. I haven't personally had a problem, so I think there has to be a specific sequence of events for this to happen, and it involves someone at BA trying to update the AS record, which is easier said than done. It may be, that had you tried to OLCI on BA, left it a few hours until well under T-24, then used the AS PNR code to check in using the AS App, it may, may work, since that is what I would normally do and and the AA version certainly works like this. The problem is that AS won't proceed until it knows that the BA check-in is complete, and it's not a live link, it's some sort of batch process. By updating the passport number - not required on AS here - then that triggers the batch process.

It's a bit obscure, but basically if this does happen again, ask the agent to update the passport number on AS at the outset. The other thing that they could try, which isn't good practice, is to split your reservation with BA cut out from AS, then reissue the BA ticket. When you get to SEA or PDX you will have further hassle there. This has other problems but if time is running out then ti's an option.

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