For anybody worried about savegames. Just make a copy of your game before you update and launch from the .exe file to play on the old version.
Alternatively, copy your 7 days folder to another location and play from the launcher there if you wish to keep playing your current game. This way, when exp drops it will update and you will retain a separate copy of the correct build for your game until you are done with it.
As always, if you're going to be playing on 177, clean out your saves, worlds and mods.