When will the next actual update come out, and will it be possible to convert our save data over to it when it does come out?
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The update is almost done, but I can't say yet when it'll be fully done.
The updates are always save file compatible. On windows, you can use update files, or move the saves from the www/save folder from the old full game version to the new game folder. Both is shown in the video below.
On android, installing the game again with the .apk updates your game and lets you continue your save.