I've just call 新華, the guy said that we can choose OX (Thailand Eastern Airline) if we depart on Dec 28 & 29 at HKD1,699 (same price as CI), and Dec 27 at HKD1,799.
Actually, I prefer to join the tour on Dec 27 or Dec 28 by choosing OX, what do you think ? I'll discuss with my husband tonight and let you know more.