I think you may want to consider a backup plan, GP mod maybe...
What's in a distributor stock or at DJI is the last of the run for P2 series new material, camera wise. Batteries are a money maker and they're made by others, so we'll have a source for them. All the electronic boards will dry up as well. The used market will be a long term source.
I believe DJI doesn't have any intentions in being backwards compatible, into the near future. This will be the same for the P3 and Inspire. At least that's how I expect it to sort out over the next 2-3 years. What you got in your hands ain't "The Future of Possible"...as it will be from others.
Good luck!