I have also experienced this in the industry in one of the projects I have been a part of. There was a change in PM due to resource constraints. We had a kick off meeting to introduce the new project manager with the existing manager present. Within the following weeks, both managers were in the program meetings and were working together offline to prepare the new PM for the transition. This involved extensive conversations around budgeting and scheduling, as well as anticipated tasks for where the project was in its lifecycle. I noticed that it took the project team (quality, R&D, operations, commercial, medical, and regulatory) a few weeks after that to function as a team once again adjusting to the new management style. I found a brief blog post that lists 6 of the biggest factors that need to be considered during project management changes. I am having issues uploaded the link. The blog post is from Tech Republic: 6 tips for a successful project transition.