Game & VR projects save at routine intervals and whenever a change is made to the script or Story Map. All of these saved versions can be accessed by using the History tool, accessible from your script editor 'File' Menu.
You can preview these different versions by selecting them from the History list.
Clicking ‘Restore’ will make the selected version your working copy. This will also revert your catalog and reports to reflect the selected version.
To mark specific versions for later use, click the 'heart' icon. You can also rename the entry by clicking the 'Autosave' title.