Recent Government report looking at An open national address gazetteer. This report is quite detailed. It covers situation at moment and how might move forward. It highlights limits of use of postcodes as already openly released in CodePoint and suggests to wider use of either Unique Property Reference Number (UPRN) and/or a fuller set of open addresses.
I myself am keen organisations move away from reducing addresses to just what is required by the Royal Mail to deliver the post; as the use of Postcodes and ‘Post town’, that are setup to reflect routing and delivering of mail, over actual localities (villages, towns, hamlets or suburbs) together with counties, has distorted much understanding of place.