For measurement the year 9s and year 10s will continue to follow the same program. This is due to the fact that there is significant cross over between the levels. There are quite a few year 9 students who are working at level 5 and level 6 of the NZC, so they need access to year 10 work. There are quite a few year 10 students who are working at level 3 and level 4 of the NZC, so they need access to year 9 work.
https://sites.google.com/view/2018math/year-10/y10-term-3-wk-1-to-5