If you thought the other updates were small, this one's so small it doesn't even have the last paragraph. This is a fix for cases where the backup save isn't corrupted, but also isn't a valid save file which can happen if it's been edited using an external program. Fingers crossed this should finally for real for real be the end of the save data issues, but if you're STILL having issues where you can't start the game please let us know on our discord.