Hello Nicole!
For the first patch we uploaded manually a new build, but you CAN get back your old savefile by Copying the "SaveFiles" folder in the old version of your game and Paste it in the new folder.
We now have learnt how to use the auto updater, so if you have the Itch app it should now update automatically and normally it shouldn't erase your savefiles.
This was a trial and error process and we're super sorry for the inconvenience :/
Glad you're enjoying the game overall <3
Lola