DX11 default startup on GFN questions

im playng on free GFN and i have a question, is paid version have a start up with dx12 or same as free one, with dx11?
i am like switching it up to dx12 every time i want to play.
is there a technical reason it doesnt start up with dx12?
dx12 is even selected as "default" in the game itself and still start up with dx11
mayb it's a "me" problem and i didnt switch something i settings? i was looking for it but dint find anything