Slight change that's made it a little better.
Now it seems there will be about eight hours delay between my train arriving in Xi-AN and my plane leaving. They have promised me a hotel room where I can get a few hours sleep before heading off to get the plane.
And it seems I won't have to work until Tuesday, so a slight improvement.
And, looking on the bright side, this delay has given me a chance to watch the new Star Trek Continues episode - "Lolani" which was really rather good. Definitely true to the original series.