Also, sometimes the DL site doesn't show you all of the LTU (XV) fares when you are doing the search using the companion certificate search. I've had situations where I'll look first to see what the regular price of the tickets I want is and what classes are available. I'll then click through the certificate, and some of the same tickets that I just found don't show up. If you call, mention the website issue, and they have booked the LTUVX tickets.