Checking In for Codeshares
 

I bought an AY ticket a few months back for roundtrip flights totally operated by BA. The translant was an AY codeshare, but the EU flight was just sold as a BA flight number. Neither BA nor AY let me check in online & upon arrival at the airport, BA didn't initially see the full itinerary (BA thought I was stopping in London).

What gives? It's the same PNR on both airlines with all flights operated by BA, so why is BA having trouble viewing the itinerary?

As you write yourself, "BA was initially.." = I read that in the end it was ok. Just an incompetent CI agent as clearly the full ITN was in the system, wasn't it? ..online CI is another thing and can indeed be an issue with codeshares. not just within OW but in general as well.

Wouldn't say so. Sometimes connections are not showing (for some reason) in BA system and those needs to be added manually during check-in process.

In my experience this tends to happen especially if flight is AY ticketed but mix BA/AY/AA marketed.

Yes - the CI agent cleared it all up. Just wondering how this system works such that it didn't have everything linked together. When I viewed my itinerary on ba.com, I could see all 4 flights. Additionally, although ba.com said I could assign my seats online, I couldn't actually do so for the BA (non-codeshare) flights. I could, however, select seats for the BA-operated AY flights.

Strange...