Originally Posted by pauldb

You'll need to ring avios.com to book it as one open-jaw booking in one go - you can't do that online. (Search for availability as one ways but don't complete that way or your voucher will be half-wasted. Don't be misled by the low taxes on a HKG-LON oneway either: that won't apply to your ex-UK return. The taxes LON-PVG-LON or LON-HKG-LON return will be a better guide.)

Yes the PVG visa is on arrival - can take a little time but it's well trodden if you show your onward booking to HKG (or any other third-country).