I assume you're looking here.
https://www.immigration.govt.nz/new-...sa-application If that's it, notice that it says 95% of applications are completed within 86 days, and that's different from saying that it's a maximum - INZ never set a limit on themselves, because every case is dealt with individually. The CO verifies everything stated by the applicant and by the employer, often by getting responses from third parties, who don't necessarily find it urgent to reply quickly to the questions asked. Also, no timing given by INZ, either on a web-page or by one of their officers, is EVER a promise, only their best guess at the time, based on recent averages.
So yes, for that reason and because the holiday season is approaching, it IS possible that your application could take longer.
I understand that you're very keen to know what is going on, and particularly, to get your visa. In your place, I would be thinking about doing two things. I would write an email to the CO (or to INZ with all your application details to get it to the right person, if you don't have a contact email for the CO), pointing out the length of time it is since you applied, and since the contact with your employer, and asking if there is any further evidence or information you can provide to help him/her advance your case. And I would phone INZ again, to see what they can tell you now about the stage things are at.
If your processing time goes on beyond anything mentioned, you can complain
https://www.immigration.govt.nz/cont...aint-about-inz, which goes to the branch manager in the first instance, and draws his/her attention to the fact that you have a problem.
Holiday closing.
http://www.vfsglobal.com/india/uk/public_holidays.html