I just came back from a tour and was on both of these flights. However, and it's a big but, we flew business. CA economy appeared terrible enough from reviews that we paid for the upgrade. If this is an option for you, check with your tour operator about availability and cost.
The flights are still on the combi 747-400s. There is no AVOD in economy. There is AVOD in J and C. I understood the food was inedible in Y so bring your own. Food in Biz was surprisingly decent and plenty of it. It was much better SFO to PEK than reverse.
Check seatguru.com for pitch in Y. Any other questions, just ask.
And welcome to FlyerTalk.