Stevie, analyse what you are saying or feeling. At a best guess sounds like it is over turning on the onside? There are fin adjustment 'solutions', but most likely its you and you need a keen eye to pick up an embedded habit that's stopping you progressing. Don't mean to be harsh. See if you can get a friend to video and slow mo it.
If its any consolation, I run a 2016 vapor in UK water. I have got use to its 2 stage turn on the onside, I have smoothed this out a bit with a CG fin that I had lying about! If I reach to the pylon its cool, gives me everything I want, reach further forward (climb over the front)and it will be a handful, it will break me in half with too much angle too soon.
Matt Southam (Xtreme-gene, spain) is a radar skier. Take a cheap and cheerful flight to Spain for a few days, he will sort you out. I have just been out there for 4 days and had a blast, but most of all he sorted some subtle issues that I was not aware of. (See the pic on the website, *Rob ...........*)
I also like retail therapy, in the last xx years ... CR7, sixam 2 pt, sixam ss, HO A3, D3 Q45, Denali 3.4, Denali c65, Vapor 2016. Sometimes a new purchase re-boots the system ! All of the above I have run into 12m bar the C65 which I never made friends with. Sixam 2pt I ran 12 and had a futile attempt at 11.25. I bought the vapor off e-bay last year just because of frustration with the last purchase.
It will take you most of the season to adjust to the new stick, and find you still have the same problem! Concentrate on you and you will ride this out.