This should not happen. The Cabinet Manual requires that advertising "should not be conducted in a manner that results in public funds being used to finance publicity for party political purposes" and that it be "free from partisan promotion of government policy and political argument". It also refers Ministers to the State Services Commission's guidance to departments in an election year, which includes specific guidelines on election-year advertising:
in the run-up to an election, agencies should carefully consider the content and timing of their campaigns. Successive governments have exercised restraint around advertising campaigns to avoid any perception that funds are being used to finance publicity for party political purposes.
Communication campaigns or advertising undertaken during this period should be assessed for potential perceptions of ‘party political’ bias. Agencies should be aware that content, which might be unexceptionable at other times, may take on a party political flavour in the lead up to an election.
In the context of an election campaign, where the handling of the Christchurch rebuild is a significant election issue, an advertisement saying what a great job EQC has been doing (which would be unobjectionable at other times) inevitably takes on a party political tone. To do it 20 days before polling day smacks of interference.
It will be interesting to see whether the Minister was involved in this advertisement, and whether any assessment was made against the SSC guidelines, and I've sent in an OIA asking for this information. But while I've asked for urgency - abuse of government advertising during an election campaign being the sort of thing there is high public interest in - there's next to no chance of it being released before the election. No department is going to want to upset their Minister by embarrassing them during an election campaign, and no Minister will sign off on release until the polls have closed. Another example of how political interests undermine the OIA.