The staging discussion is centered on these scenarios:
New Deployment: New drivers and applications are developed during the development stage, then they are tested and moved to the test setup. These applications are put together and moved to the production setup.
Existing Deployment: You already have a development, test, and production setup ready and you want to move a new policy from the development setup in the production setup.
Existing Deployment discussion is not scoped for the current version of this document.