There is more than one person who uses this site and has this name.
One of them is shown below, you may mean a different one:
This person's Freedom of Information requests (approximately 2)
Hopefully this is a complete list, as of 7th January 2016. No guarantees that they are all here.
The 'real' address of PO Box addresses has always been available and renters of PO Box addresses are made away of that when they apply.
This person's 2 annotations
Just to update this:
Matthew Somerville has built a tool to add the locations of all the postboxes.
Edward, that's fantastic work! Will you be open sourcing the code you used to scrape the site so we can update it when the post office close more branc...