Check out How to Model Change: 3 Types of Business Change by Christopher Smith. Here is an excerpt:
How do you model change in business?
Well, it depends on the nature of the change.
Perhaps you’re acquiring a company … or perhaps you’ve been acquired.
Maybe you’re adopting a new software platform.
Or maybe you’re changing your revenue model.
In each of these cases, the way you model…
The full article is available here.