I say ditch the jobs and head to ruapehu or down south if thats where you want to be, so long as you can afford it you might as well do it while your here! Ruapehu is covered with snow at the moment and its gorgeous!!! We get a view of it on a clear day from our new flat :D
You may even be able to pick up some bar work or something whereever you plan to go, if your in the north island try maybe taupo, ohakune or wanganui, or maybe even taihape for jobs, although ohakune is rather tiny, but I hear it has a pretty decent night life for a small town at this time of the year.
If you do plan on staying in the north island and heading up to the mountain or staying anywhere near it give me a PM or if your on facebook add me and keep me updated, I live about 1.5hours away from Ruapehu