Virgin Miles on Air New Zealand from the UK

Hi,
I am planning to travel to NZ for the Ironman World Championships in November next year. I currently have 135,000 miles and will have a lot more in the next six months. If I look at flights on the Air New Zealand website, the taxes and fees only seem to be £200-300.
So a couple of questions:
- Are the taxes and fees likely to be the same when booking through Virgin with miles?
- Is availability OK when you book a long time in advance and are quite flexible with exact dates? (I think November is normally low-demand)
- Are there any pitfalls I should be aware of and avoid?
Thank you!
I am planning to travel to NZ for the Ironman World Championships in November next year. I currently have 135,000 miles and will have a lot more in the next six months. If I look at flights on the Air New Zealand website, the taxes and fees only seem to be £200-300.
So a couple of questions:
- Are the taxes and fees likely to be the same when booking through Virgin with miles?
- Is availability OK when you book a long time in advance and are quite flexible with exact dates? (I think November is normally low-demand)
- Are there any pitfalls I should be aware of and avoid?
Thank you!