Originally Posted by trek87

I don't know much about the KVS tool, but this seems to be consistent with the way I would expect airline reservation systems to work. On the airline's website, if you're trying to book AAA-BBB-CCC and all of the seats from BBB-CCC are gone, the website would tell you (unless there was a direct option or the search engine finds you an alternate routing) AAA-CCC is unavailable, even if you could get from AAA-BBB.