 In the years following expulsion, the Singaporean number plate system evolved independently with changing prefix systems since 1972, culminating to the reintroduction of the "S" series for private cars in 1984, the inclusion of a fourth checksum letter, and varied colour schemes for different classes of vehicles.The "L" series began to be issued to Labuan in 1906, a then-independent island outpost off the coast of British North Borneo under the British North Borneo Company that would later become part of the Straits Settlement in the following year.The "L" plate was discontinued in 1963 after the island (now part of North Borneo/Sabah) was reformatted in accordance to North Bornean/Sabahan conventions, and would remain unused until after Labuan's status as a Federal Territory in 1984, when the "L" series was reinstated for the island.