They went constant curve in race masts earlier, and 2017 is the year they changed to constant in everything.
I have a 2017 GA Cross and it sets magnificently on an old generic 430 RDM that is constant curve. Thus I presume the masts are pretty well middle of the road in that year.
To be safe, maybe try the different years unifiber charts. Or, windsurfing perth would know for sure