Erm, the same question was asked 10 years ago, about the end of FSX..

Pete Dowson has said.. 'There will be an FSUIPC5 for P3D4, but first release won't coincide with the rather rushed (in my opinion) release of P3D4 on Tuesday. And FSUIPC5 will be a new product, not an upgrade. It's been too much work to have it as just an upgrade. The user weather stuff is stripped out, and some other facilities do not yet work (mouse macros, menu diversion, frictions just to name three). They are dependent on further P3D development. '

So, there you are..