Same here. Tried the beta, and reverted because there isn't a single player looking for a multiplayer game in the beta patch.
Now I can't load any save at all, the game crashes when I hit the "resume game" button on the menu, or the "load" button when playing.
I tried deleting all my saves in the saves folder, but it's not working. Does anyone have a fix for that ?
I tried reverting back to the beta branch, but same error, I just can't load anything anymore. I also tried to verify game cache on steam.