BACKUP YOUR ENTIRE GAME AT THIS VERSION
--for anyone unaware, ea has been bought and is now owned privately. this simscommunity article from before the confirmation hit, breaks down a bit why its concerning/who is now in charge.
Genuinely yall make sure to install the current version of sims 4 in a secure place as a backup. maybe make 2.
Backing up your files for the EA app: (thanks so much to @taanoir for testing this! (please feel free to comment if this does/doesnt work for you so folks can check the replies!)
make a copy of your Documents sims files and your general game files (usually located in your program files. you can go to your sims 4 settings in the launcher to see where your installation path is, if you dont know!)
put a copy of these files on an external hard drive (or maybe another drive on your pc titled as your back up, with the version number ideally so you can double check!)
now if your game accidentally updates or you update on purpose and want to revert, you simply copy paste these backed up folders back into the respective paths. i.e. your backed up documents folders back into the documents directory, program files in program files where your game is. and override! Taanoir who tested this, reported that this successfully reverted the version of the game for her and she was able to start it in offline mode again (to not get the update)
Also! grab any mods you enjoy for the current version, any you considered trying out with it. back them up.
if future updates ruin everything, we likely cant go back or get older versions of the game OR mod versions easily anymore. BACKUPS ARE EVERYTHING
worth making sure we have a safe copy of it somewhere JUST in case. seriously, better safe than sorry!
Edit: one trick to launch offline as an EA Launcher user without needing to unplug anything but ensure the launcher cant mess you up
you can unplug your internet/turn your wifi off beforehand on your pc. This requires you to Remember to do it, sadly.
one way you can turn your internet off without needing to unplug/leave the pc is the following
(im using win10 still) you can navigate to the Settings for your pc by pressing the windows button and clicking the Cog that says "Settings". Navigate to "Status". there you should see an option say "Change Adapter Options". this opens a new window that should have a little screen icon with "ethernet" or the like on it. right click that and click "Create Shortcut". this will put a shortcut to it on your desktop. Now on your desktop, you can right click it and click "Disable" to turn your internet connection off. to turn it back on, you can right click it and "enable" it again.
Ideally, make a desktop shortcut of your sims 4, keep the launcher off in case youre used to opening it through the launcher. Place the sims shortcut next to your new ethernet/internet shortcut. Hopefully this way seeing them next to each other will remind you to turn your interner on your pc off so the launcher cant f you over and still update...
Huge thank you to @taanoir for testing this!
addition: please if you have any ideas on backups for official versions or anything else feel free to add on in the replies! other folks could skim through and see if anything works for them etc (theres some instructions for linux someone reblogged too! check those if you run on it 🧡)