Originally Posted by
adrianlondon
Can I ask why the latter isn't valid? Surely it's a return flight ... LHR-PEK-HKG (valid for 72-hr visa) and then HKG-PEK-LHR (valid for 72-hr visa).
I stand corrected, I think you are right. I suggest going to China TWOV thread for more information:
China 24, 72, and 144 hour Transit Without Visa ("TWOV") rules master thread