BNO immigrated to China.

If your BNO card has expired, you need to apply for a new BNO card to return to Hong Kong. In addition, you also need to meet the relevant regulations and requirements of the Hong Kong Immigration Department, including holding valid travel documents and visas.

Before going to Hong Kong, you need to confirm whether your travel documents and visas are valid and abide by the relevant travel and entry regulations of the Canadian government and the Hong Kong government. If you hold Canadian citizenship, you need to apply for a Canadian passport to go to Hong Kong.

In short, if you want to go to Hong Kong, please confirm whether your travel documents and visas meet the requirements and abide by the relevant regulations and requirements.