Managing Project File Conflicts

If two users assigned to the same project have the project file open, and one of them makes an update, a notification () appears at the top of the second user's page, indicating that a newer version of the file is available. If the second user makes a change to that file and clicks Save, a File Changed dialog appears.

The second user can either:

Save their changes, which creates a new file and discards any updates made by the other user
Keep the first user's changes and discard their own. The second user can continue modifying the file after the first user has finished updating it, and saves the changes