RM had the right advice as far as following the history of a flight prior to your target date. There is always one odd aspect w/Asian flts--no show factors are so weird. There is no rhyme/reason until flt day. Many businessmen reschedule after the fact and their companies pay as necessary. Make sure you check for major trade shows and any holidays that might be significant. I suggest keeping an eye on tripadvisor HK forum for advice regarding both. HKG is an amazing city. PVG--I could take or leave it; it can be horrifically HOT and HUMID! (how does 100+ sound?)