Hi Gillespie,
I've got similar hours to you and have recently got onto the Wings course. Will hopefully be going out to NZ to start training in Jan.
If you're referring to the NZ phase, then as I understand it, depending on how many of the first 12 weeks you need out in NZ, the longest stay could be as much as 23 weeks. That covers 12 weeks for the full Foundation course then 11 weeks for the VFR phase. The only flexible is the Foundation course - once assessed by CTC they recommend how much of the 12 weeks you will need which will bring that figure down.
After those first 2 phases, there is leave and ground school for the ATPL exams back in blighty (about 4 weeks in total) followed by a second visit to NZ for 14 weeks for the IFR phase. The rest of the training is split between Bournemouth and Southampton. This covers the IR/CPL training, Intermediate and Advanced Training and includes leave.
I'm sure you will find a lot of people are in a similar position with the mrs, me included. 9 months out of the rest of your life is a small amount of time.
Hope this helps. Good luck at Stage 3&4.