E12 Manor Park: why this London postcode has the number 12

After Leytonstone, before Plaistow

Manor Park is E12 because of the alphabet. E1 is the Eastern district office, and in the Post Office's list of March 1917 the offices after it follow by name: Manor Park comes after Leytonstone (E11) and before Plaistow (E13).

See E12 on the map