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I was born in South Africa, and have been living since. My dad is British, hence I am able to apply for a British passport because I am also a British citizen (dual citizen). My first British passport just arrived to my home in South Africa.
If I were to leave Cape Town for London, showing my British passport, will the immigration stop me because there isn't any record on my British passport, "leaving" tje UK, so how could I enter the UK?