It's here today.
Yesterday was Sunday, GOG only does updates on week days, not weekends, because they need to wrap the patches on their own propietary installer and test the patches to see if they do what the changelog says they do and to check whether it breaks the game or not.
fishbaits: GOG update page just said it`s there, yet when I checked there are no patches.
Curiouser & curiouser. Hope it will be just a patch & not a complete DL again.
If you see no extra downloads, such as separate patches, chances are you'll need to download the whole game again. This is one of the reasons I use GOG Galaxy, myself -- every game I have installed auto-updates and, if the patches broke the game I can always use the rollback feature and go back to a working version of the game.