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I believe my parents were "British Subjects and Australian Citizens" as I was, on the cover of the passports years ago.
I believe I have had leave to remain since I applied for my first adult passport in about 1964. My family arrived in UK in about 1953.
I have lived here since approx 1953. My own earliest passport was issued in London on 20/03 /1964, and the next one issued in 1966 has "Australian citizen and British Subject" on it's cover.
The passport I got when I changed my name to Akin-Smith on my marriage in 1971 has a stamp which reads: "given leave to enter the UK for an indefinite period." All my passports since then have this stamp