[is this a new record in keeping an unpopular post alive - 4 out of 5 posts from the OP ? ]

WARNING: long and rambling post, but any input appreciated.

Got around to calling aa yesterday between the o/b and return.

First agent looked at it, spoke to tariffs for 5 minutes, then came back and told me that a D fare on BA was basically a KUP - 'it's a special business fare which only books into biz if there's availability in the right class'. Yeah, right, whatever, why don't you try actually reading the fare rules ? Didn't want to put me onto a supervisor ('he won't be able to get you sitting in business for this flight' ). I insisted.

Put on hold for 15 minutes while the supervisor tried to pull up the fare rules. He came on and was honest enough to be apologetic, in that they really didn't have a clue what had happened.

He said that the D fare allows them to book into econ, and is cheaper than a full Y (all that was left for sale on the o/b) - it didn't book into biz because BA didn't have any D seats available. [I think that he was trying to say that it was like a DONE fare, where if there is no D availability then you can fly in Y].

To me, that sounds like horse5hit - DEUNBA is not a changeable fare, so surely aa.com shouldn't be able to sell it if BA aren't making it available (usual aa.com/ba differences in class availability aside).

To be fair to him, he suggested that I should pass this query onto AA customer services and ask them to explain (I don't think that he really believed his own story), which I will do.

Has anyone come across anything like this before ?

Are there any instances of DEUNBA booking into economy ?

Very strange, and worrying for those of us who use aa.com for ba flight booking.