I am going to book online to mainland China for August (from Beijing ,trips to Yantai, Jinan, Shanghai, Xian,Guilin, then back to Beijing).My passport is valid until 2011,06,21 and I will get a new one within 3 weeks. If I book today or to morrow, could I use the previous passport number, because I would like make the reservations and the payments as soon as possible?

and how could I make the change when I get the new one ( obviously, the number will be different from this used when booking )? Could the reservations be cancelled because of this purpose?

Thanks you