I've booked three First Class awards with Cathay ~ two to Africa and one to Australia.
The odds of getting the exact days you want, especially between North America and Hong Kong, are not good, even booking far out, so
flexibility is important! HKG-JNB is usually wide open. Keep in mind that there are three West Coast gateways to choose from - YVR, SFO and LAX.
And if you're curious what to expect of Cathay's First Class to Africa and back, check out my
report from March 2010.
Good luck!