Originally Posted by
hkstudent
So it can be used for separately for one leg on 2 return flight bookings?
The reason why I avoid to do CW on ex-LHR leg is to avoid horrible YQ and also massive APD, which HKG at least have good saving on YQ (not airport duty + 3rd runway surcharge)
For one person, you can use it for both legs of a return, or for a one-way. HKG is a unique situation where you might opt to just use it for a oneway.
HKG only has YQ saving on tickets originating in HKG (and I think UK APD is the same for WT+ as CW). If you book the return option, you'll still pay hefty YQ on HKG-LHR CW because it's ticketed LHR-HKG-LHR. This only way to avoid that YQ is to book HKG-LHR separately: hence LHR-HKG without the voucher and HKG-LHR with the voucher (the latter by phone).
I suppose if you are back-and-forth to HKG you could book a later eastbound at the same time, maybe --- HKG-LHR-HKG with the voucher.