Plans rarely go as planned. Things change, circumstances shift, people break their promises, and lawmakers can change the basic rules of the game.
This, of course, doesn’t mean that you shouldn’t plan. You most certainly should have a general idea of where you’re heading and how to get there. But you should also be ready to take an entirely different approach.
So go ahead, plan away. But don’t be too attached to your specific plan; be ready to change it as soon as you find a flaw in it or as soon as you uncover a better way.