United Kingdom - Passport & Nationality - British Overseas Citizen (BOC) - Ceylon Upgrade
Ceylon gained its independence from British rule on 15.11.1948. The new Constitution of Sri Lanka stipulated who and who didn't become Sri Lankan citizens. Many thousands of residents in Ceylon at the date of Independence did not become Sri Lankan citizens, and these people, by law, became either British Subjects or British Overseas Citizens. In some cases, a person was automatically a British Citizen.
Where an applicant was born before Sri Lankan independence on 15 November 1948, then they may have a claim to the British Overseas Citizen (BOC) status if their father was not born in Ceylon. In most (but not all cases), this occurred where the father was born in India. It may be possible to upgrade this to full British Nationality if the applicant has a grandfather born in the UK, or the Right of Abode in some other manner.