Check out Drastic Measures: When Change Management Requires a Change in Management by Christopher Smith. Here is an excerpt:
What’s the difference between “change in management” and “change management“?
A lot, actually.
Let’s look at what each term means in more detail.
What Is “Change in Management”?
“Change in management” simply refers to a personnel change. In other words, replacing old managers with new managers.
The full article is available here.