BNO Visa 的法例仍在草案中, 未 finalize
根據這個網頁, 如果想 5+1 (6 年) 後歸化做英國公民
5 年內不可離開多過 450 日
平衡每年不可多過 90 日
即一年可以返香港最多 3 個月
British Citizenship by Registration or Naturalisation
After being settled for a year, BNOs can apply to register as British under section 4 of the British Nationality Act 1981, and adult dependents can naturalise as British.
It is worth noting that there are stricter residency requirements of no more than 450 days outside the UK during the 5 years prior to the date of application, and no more than 90 days outside the UK in the 12 months prior to the application.