I used the data given on https://osm.mathmos.net/addresses/post-towns/PR.html and the advice on https://wiki.openstreetmap.org/wiki/Addresses_in_the_United_Kingdom as a guide to making the changes. I can change these addresses back if you want but be aware that the addr:* tagging is intended to map the *postal* address only and the keys settled on have been reached by consensus. Sometimes this reveals the arbitrary way that Royal Mail assigns postal towns, and other aspects of addresses, which can seem odd. If you want a *locational* address then Nominatim or the query tool handles this, eg the "Enclosing features" for Garstang would be: https://www.openstreetmap.org/query?lat=53.9016&lon=-2.774 (scroll down in left-hand pane) but its post town (addr:city) is Preston.