Complex sentence: He was President of the Royal Philatelic Society London (RPSL) since 1934 when he accepted in October 1936 to succeed to Edward Bacon, the Curator of the Royal Philatelic Collection.
Split into simpler sentences: He was President of the Royal Philatelic Society London (RPSL) from 1934. In October 1936 he accepted the offer to succeed Edward Bacon, the Curator of the Royal Philatelic Collection.