Coastal North Island NZ

I'll be starting in Tauranga but others can join in from anywhere along the route. Plan is to go south first and then as the winter starts to kick in we'd be already in the north. The round-trip is about 3,000 km which will need 30 days of cycling and 15 days of R&R. This is the proposed route: https://goo.gl/maps/1vDWCqxGTjE2