I actually think that both contracts will well serve the needs of both services and the nuances of their requirements in the years ahead including when joined in a coalition taskforce.As stated Mr C the build contract was $640 for 2 plus a $250 sustainment contract for 5 years.
The white paper allowed 1.2b so I'm presuming that's a contingency. What's relevant is a contract to build cf a contract to build whatever IHI have signed for.
The RNZN have done their homework on this and the project has obviously been scoped as a stream of outcomes in a collective NZDF sense that references partner nations.