:::I'm a bit confused about what legislation you're referring to. AFAIK this is simply an executive decision, made under existing legislation and simply requires the NZGB to gazette the name in a notice. Now evidentally they are waiting legislation because the current legislation would require both official names be used (see FAQ 2) and the name hasn't been gazetted but this largely isn't a legislative issue (and if the Minister had decided on Whanganui solely I presume there would be no need for any legislation). I would also point out there is no change to the official (central) government name since as was pointed out numerous times during this process and is e.g. in the FAQ there is no official name and this was one of the reasons the NZGB decided to look into the naming issue. In terms of common names thing, it's not entirely clear how this plays out. The preference is apparently for Wanganui in the area covered by the council (at least among people who cared enough to vote in the referendum), outside there it's less clear