Yate maintains three versions of the metadata in a file. The initial state represents what was in the file when first loaded or after being saved. The current state represents the current possibly unsaved metadata. The editing state represents the metadata at a particular point in time.
In the UI the editing state can be manually and automatically updated. Also you can restore to the editing state as opposed to the initial values.
The Update Editing State statement, copies the current metadata to the editing state.
The Revert to Editing State statement, copies the editing state metadata to the current state. Note that if an editing state has not been established, the initial state will be used.
An interesting point to remember is that while the initial state is reset when a file is saved, the editing state is not. It is therefore possible to revert to a state before files were saved.