[2021] NOT FIXED: UPlay intermittently downgrades the game from v12 to v11

Missing menu text? Missing Save Files? This is caused by UPlay Connect downgrading your game to an older version, which is incompatible with Save Files made on the latest version of the game.

My solution for resolving this issue?

1) Configure UPlay to not automatically update Anno 1800.
2) Load the game and check the bottom right corner of the Main Menu, the version number should begin with "12". If it starts with 11 than that means UPlay has downgraded you to an old version of the game.
3) When looking at the game information in UPlay the green button to launch the game should say "Play", click it to play the game if it says Play.
4) If the green button instead says Update feel free to check what patch it'll download however if the update is 466MB's in size you should cancel it immediately! 466MB update is an old v11 patch and will downgrade your game from v12 to v11.
5) If it *is* 466MB's and you've cancelled the update you might be wondering how to play without downloading that old patch right? Easy. Open and close UPlay repeatedly until the green button for Anno 1800 says "Play" and then click it.

The latest release of the game will have a version number that begins with the number 12, the version number is displayed in the bottom right corner of the Main Menu. This 12th major update is required for some Season Pass 3 content to be playable and for you to access your Save Games that were made while v12 was installed.

If you had upgraded to v12 and then later you were accidentally downgraded to v11, most text on the Main Menu and other areas of the game will likely be missing. Re-upgrading to v12 will fix this. Verifying your installation will also fix the missing text, but it won't necessarily re-upgrade you to v12.

Done, I hope you have fun!

Oh also when setting up a game leave Fog of War enabled to avoid notable issues present in the current release of the game.

Current working theory is that there is a caching server with an old copy of the patch that Uplay intermittently connects to, why UPlay allows it to be installed over v12 is anybodies guess (why does UPlay perform no version check before downloading and/or installing stuff?).