I got a reply back from case office, after mailing for an update
Your application has been transferred to Immigration New Zealand’s Specialist Assessment Team (SAT) in Porirua, New Zealand for additional verification. You may be requested to provide further information. Once this process has been completed, your application will be finalised. You should be aware that because your application has been transferred to SAT, it is likely the time taken to assess your application will be longer than the published processing timeframes. An Immigration Officer from SAT will be in contact once your application has been allocated.