The grandchildren of British citizens who have left the UK to live permanently overseas are eligible to come and work or pursue self-employment activities in the UK under the British ancestor route. This route is relevant to the applicants of the British descent who are not eligible to register themselves as British citizens.
The applicant under this route has to demonstrate adequate maintenance and accommodation while in the UK. Entry clearance needs to be sought while outside the UK and before arriving to the UK.
This option is an attractive route as it leads to settlement in the UK after five years of residence and work/self-employment in the UK.