You can replace a referenced file with another reference without changing existing edits to the reference.
To view files that have been recently replaced, a reference in the Outliner or Reference Editor, and then select Reference > Recently Replaced Files. You can then quickly revert back to any previously replaced references by selecting the file.
Except where otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License