i hope you dont make the game only directx12. (or vulcan)
The plan was to have them both in the same build and then add in the ability to swap between them while ingame once Godot added that feature. But there seems to be a lot of people that are having issues with dx12 so I'll be stripping it out of the vulkan build completely from now on.
There will still be a dx12 version of any given build just in case people are having issues with vulkan though.