I've just looked at this, and I am concerned that you are all taking a very wasteful approach, labour-wise and time-wise, to preparing mulled wine. It behoves you, as people of frugality, to be sparing with your time and effort, as well as your dosh. And you know that buying and preparing in bulk is much more economical.
So, given you are going to adulterate the wine with additives anyway, buy a chateau cardboard to make mulled wine out of. Invite friends around. Make sure you have a couple (no more than 2 should be required) of empty wine bottles with screwcaps (almost all NZ wine has screw caps and most NZ wine is of a good to high standard - plug for home country - so buy an NZ wine or two). Make the mulled wine with chateau cardboard, consume some with friends, decant remainder into previously emptied NZ screwtop wine bottles (this step does require some pre-planning, but I am sure you will manage!), and invite friends to return on the morrow. Repeat till all mulled wine is gone. And then start again. That should make winter appear to pass rather rapidly.