yes my father and mother lived in Kenya and my mother was living with him as his dependent as she always i.e my mother was holding british passport my father was a kenyan citizen as he renounced his british citizenship. i also lived in kenya but migrated to canada in 2004 and have lived in canada since . my father died in 2005 and i brought my mother to canada to live with me i couldn't get her status done in canada as the requirement is to apply from country of residence or citizenship .upon my fathers death my mother lost her status to stay in kenya and the british high commission in kenya refused to help i was forced by circumstances to bring her to canada as i was refused viza to accompany my mother , i made a second attempt to resolve my mothers issue and went to london in 2009 , i did tell the uk , london immigration officer my mother is a british citizen , and has no status in canada and i want her matter resolved , the immigration officers were not prepared to listen and put a refusal to enter britian on my canadian passport the immigration officers did see the certificate of registration as a british citizen of my mother despite that they put me in holding cell and put me back to canada in the next flight , it was a horrible experience for me.
Bottombline we lived in kenya and i migrated to canada , and we don't have any property in uk.
I think you require a specialist in immigration law for this matter - it is not a simple question of entitlement to NHS treatment and social services assistance.
I shall opt out and hope one of my colleagues can pick this up for you.