Kenya Uganda Tanganyika. Definitives. Issued from 1 June 1954. The 15c was reissued 29 April 1959 with a dot under the ‘c’ of the value.
The issue is most famous for the 5c and 30c used examples with inverted vignette. These are extremely scare with just one example of the 5c known and three of the 30c recorded. Despite exhaustive searches no other examples have surfaced. And to date there is still no consensus as to how the errors could have occurred, but it seems likely just one vignette was inverted (although correctly aligned) in relation to the others on the affected printing plates.
Another major error exists on the 20c. It is known imperforate and was first reported in the 15 March 1957 edition of Stamp Collecting. The source was traced to a Nairobi hotel employee who had purchased the stamps locally and used a quantity to post letters on behalf of guests. Around seven mint pairs and three used pairs exist.