I'm flying DTW-ORD-LHR this afternoon...

MMB shows me the big "Check in now" button, but as soon as I hit it, I get "your first leg is on American Airlines, please use your AA record locator to check in for this leg, and subsequent legs on www.aa.com".

I obviously don't have an AA record locator (because it was all booked through BA, including the ORD-LHR leg on BA metal). This'll mean that I'll have to fight my way past the AA "desk dragons" who'll demand the record locator that I don't have. They'll only check me as far as ORD, which means I probably won't be able to get on the new "BA Express Bus" to the BA terminal.

I also don't get the chance to move my seat (now that OLCI is open). Obviously upgrading any of the legs through MMB was also completely out of the question.

None of this is a biggy, but it's all a bit tedious on what is essentially a BA flight, booked through BA.