Please tell me this is true.
There must be a way to trace if those leaving with BNO passport also have China issued passport. The China issued passport can then be revoked.
It's complicated. I think a passport it's a travel document. I think for those who was born AFTER 1997 should/could not apply for a BNO. only those born before 1997 can apply. And since most of all these used condoms are students which mean they would be 24 years or younger meaning they would have been born after 1997.
I think for those born before 1997, they can apply for both Chinese and BNO.
Here's my British and Chinese passport
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When they leave Hong Kong, they need to present one passport. So I take it most of these used condoms would be presenting their BNO to leave Hong Kong, and enter the U.K. although technically, they are supposed to use their ID card to do so (I was told off in no uncertain terms when I return to Hong Kong and use my British passport because I wanted to be together with my wife and children who don't have an ID card. I was made to stand in a different queue to enter Hong Kong using my ID card).
So I'm not sure whether or not there is a link between the two passports in the Hong Kong government office. I hope there is, and hope the authority would put the two together and cancelled their Chinese citizenship. Although technically they can't cancelled their ID card as it is their right (like me) to have Hong Kong citizenship for life.