Originally Posted by
Cathay Boy
If this is true CX is breaking make security risks. The whole point of customs check is for a nation/place to know who entered and who left. If I entered to the departure side, HK knows I left, but if a CX agent let me back to landside, HK has no idea I've reentered. I really doubt CX will take down my name and passport info and report to customs.
No no no, HK does know you reentered the city so don't get me wrong. What I meant by "backdoor" is that the passenger will be taken to a place so that the immigration process for entering HK can be completed again, maybe there is a special passengway from airside that leads to the immigration hall of the arrival level.
One time I was trying to go to Mainland China through a border-crossing in Lok Ma Chau (northern outskirts of HK), only to find that my
huixiangjing (direct translation: "go-home card") expired when I got to the Mainland Chinese immigration checkpoint. I was escorted to a special office through a passageway by the customs staff in order to allow me to get back into HK. There has got to be something similar at HKIA.