JusTiCe8
Yes, I guess I am, like many other game developers, but this may be required to create video games ! In a way, it reminds me of countless hours I spent to improve my own times in Trackmania (I do have a big table of them all, check the PC/TRACKMANIA part of my homesite). I still do from time to time... I recorded videos to attest every improved level time so if you need one of them, just ask me.
To answer your question, the content of saved files will no longer change so, yes, you can keep and use them the same way in next release (v1.1).
One important thing, though : so far, the directory path where these files are created contains the version of Godot current project (Hop! 2D 1.0). So, if you launch v1.1, the game won't directly "see" the v1.0 files. That's why I decided the saved files directory path will now simply end by "Hop! 2D" without the version number to avoid any future compatibility problem. That's one of incoming v1.1 changes.
So, assuming that you use Windows, if your files are saved in C:/users/(your name)/AppData/Roaming/Godot/app_userdata/Hop! 2D 1.0 directory, You will have to rename it C:/users/(your name)/AppData/Roaming/Godot/app_userdata/Hop! 2D so that these files are correctly detected by the game. Remember to unhide all hidden directories or they won't show in your file tree.
No more renaming will be needed for possible next updates as the version number will only show in game screens.