This is a old thread but I was looking for advice on the sleeper train from Beijing to Xi'an. I was going to take the overnight train out and then fly from Xi-an to somewhere else on my way out. How far in advance do I need to book? I would be doing it at the very end of June/or the first few days of July? I will spend three nights in Beijing first and would want to catch the train the night of the fourth day. Does this allow enough time for booking the soft sleeper at the train station or I need to book further ahead?