Are you playing on the itch io launcher or via website download?
If it’s via the itch.io launcher then the newest version’s files are now in the ‘GROVE’ folder (no version number). Go to the game icon within the launcher, right click and there should be an option to open the location of the game. Your previous version’s saves should be located in the folder there.
If it’s via the website, unfortunately the key due to how RPGMaker stores its files, the save directory is located within the downloaded Grove folder itself, and will require a transfer between every version update.
Make use of the save transfer guide here for both the launcher and the web download: https://twitter.com/regalbuster/status/1614947014068035586?s=46&t=3pZFQ072drfeb9tkDv8O1w
We’re hoping with the 0.308 update that future saves won’t need to be transferred again via the renaming of the grove directory, but do let us know if you run into any further issues.
-RegalBuster