Temporarily Changing Hierarchies in Projects Implementation Options

Are there any issues and or programs that need to be run in order to make a temporary change to the hierarchies in the Implemenation Options setup?  I want to do the following but not sure what the ramifications are:

1.       Copy the existing “Original” Hierarchy (Named Copy)

2.       For all Operating Units pointing to this Hierarchy, change the Hierarchy to the new Copy one in the Projects Implementation Options

a.       Default Reporting Organization

b.      Project / Task Owning Organization

c.       Expenditure/Event Organization

3.       Go Back to the “Original” Hierarchy

a.       Add a new subordinate to an existing organization.

4.       Go Back and revert all you changes from step 2, back to “Original” Hierarchy