boundary=postal_code
I don’t have a strong opinion on the boundaries. I may lean towards adding them if they can be technically and legally. They may not be official in GB, but they exist in some fashion. And OSM has decided that the data is useful, we shouldn’t exclude the country. The rest of the world has to normalise there data to OSM/GB concepts all the time. Then again, if we had enough addr:postdcode, can’t they be computed? How important is it that we store them?
postcode centroids aren’t physical, we should delete them
Instead of deleting them, we should just add them to something physical, eg a building.