It is quite likely that your mother is a British citizen, based on her birth as a CUKC in a British colony or protectorate (Kenya) and her Right of Abode (ROA) by descent from her British-born grandparents.
As her ROA was by descent, her British citizenship (after 1983) is also by descent, under
Section 14(1)(b)(iii) of the British Nationality Act 1981;
14 Meaning of British citizen (by descent).
(1)For the purposes of this Act a British citizen is a British citizen “by descent” if and only if—
...
(b)subject to subsection (2), he is a person born outside the United Kingdom before commencement who became a British citizen at commencement and immediately before commencement—
...
(iii)had the right of abode in the United Kingdom by virtue only of paragraph (b) of subsection (1) of section 2 of the Immigration Act 1971 as then in force (connection with United Kingdom through parent or grandparent), or by virtue only of that paragraph and paragraph (c) of that subsection (settlement in United Kingdom with five years’ ordinary residence there), or by virtue only of being or having been the wife of a person who immediately before commencement had that right by virtue only of the said paragraph (b) or the said paragraphs (b) and (c); or
The relevant
Section 2 of the Immigration Act 1971 then in force states;
2 Statement of right of abode, and related amendments as to citizenship by registration
(1)A person is under this Act to have the right of abode in the United Kingdom if—
(a)he is a citizen of the United Kingdom and Colonies who has that citizenship by his birth, adoption, naturalisation or (except as mentioned below) registration in the United Kingdom or in any of the Islands; or
(b)he is a citizen of the United Kingdom and Colonies born to or legally adopted by a parent who had that citizenship at the time of the birth or adoption, and the parent either—
- (i)then had that citizenship by his birth, adoption, naturalisation or (except as mentioned below) registration in the United Kingdom or in any of the Islands; or
- (ii)had been born to or legally adopted by a parent who at the time of that birth or adoption so had it; or
(c)he is a citizen of the United Kingdom and Colonies who has at any time been settled in the United Kingdom and Islands and had at that time (and while such a citizen) been ordinarily resident there for the last five years or more ; or
(d)he is a Commonwealth citizen born to or legally adopted by a parent who at the time of the birth or adoption had citizenship of the United Kingdom and Colonies by his birth in the United Kingdom or in any of the Islands.
If the UKM question is about yourself, the first question is whether you were born before 1983. If you were born on or after 1st January 1983, Form UKM is irrelevant to you.
If born before that date, then to the best of my knowledge, you would not be eligible. Form UKM requires either one of your parents or one of your grand-parents to have been born in the UK. To the best of my knowledge, it does not allow an indefinite descent in either the paternal nor the maternal (via the
Romein judgment) lines.
As an aside, precisely how is/was Kenya a special case?
I am not a lawyer or immigration advisor. My statements/comments do not constitute legal advice. E&OE. Please do not PM me for advice.