I know there are sometimes point of sale issues so that inventory that is say visible to LH (on staralliance.com) is not visible to UA.
http://www.flyertalk.com/forum/unite...-airlines.html
http://www.flyertalk.com/forum/unite...ut-not-ua.html
However, in this case, it is A class not D class, and the flight shows up on staralliance.com AND on united.com with plenty of A availability ...
Anyone have any insight here?