When politicians do things they do not make it too obvious for common citizens.
No politicians would ever state they are leaving Brexit using what I mentioned. That would be political suicide. Refugees illegally come through South Europe. Naturally they would choose the wealthiest EU Nations to take refuge. Germany, France, UK are their favorite choice. UK saw the foresight and decided to leave though with a potential financial hit. That's why I think extending the HK BNO passport to six years and provide a possibility of citizenship was a short term solution to gain some loyal workers and money from some of these HK separatists.