u/No-Log664

So just as you I forgot to do the trick to make the game never update itselft. And today they updated it, just a bunch of useless features noone asked for. So if you are looking for solution just as me - I found this little guide on nexus discord a few minutes ago. Posting so it may help someone else as well

First of all u need to open steam console. Press win+r and type steam://open/console. Alternatively right click on start and press run and insert same command. Then type

1. download_depot 489830 489831 8442952117333549665
2. download_depot 489830 489832 8042843504692938467
3. download_depot 489830 489833 1914580699073641964
4. Enter them one by one: Copy and paste the first command into your Steam Console and hit Enter
5. Wait for completion: Do not enter the next command until Steam explicitly prints a message saying "Depot download complete". These downloads are multiple gigabytes and take time
6. Locate the files: Once all three are done, look at the text paths printed in your Steam Console. They are usually stored in your main Steam directory under \steamapps\content\app_489830\
7. Overwirte your game folder: Open those downloaded depot folders, copy the contents inside them, and paste them straight into your active Skyrim Special Edition game folder, overwriting everything when prompte

P.S - I havent tried that yet, but Ill write update as soon as I verify everything works perfect and all mods are in place

UPD - It just works. Well initial start and everything seems in place, it shows old version, but maybe some more mistakes appear in the future? Who knows, for now good to go

Edit: DONT FORGET TO disable automatic updates of skyrim, otherwise you will most probably crush in main menu. To do that locate appmanifest_489830.acf in steam/steamapps, right click - properties and set mark for read only. Also you can in steam settings set game to only update if you launch it, and you never use steam for that so... If you are interested of what to do if you want to lauch game from steam and not skse (not sure why but well) you can ask ai or whatever about how to do that