almost 3 years ago - /u/ - Direct link
After the final release on June 8th, you'll be able to continue your progression in the game.
Note that those saves will be marked by a flag to indicate that they can contain a lot of sidequests you missed along your journey.

The following disclaimer will appear to inform you :

"WARNING: You are using an early access save, we highly recommend creating a new save to have the best experience of the game. In addition, you may experience issues and bugs related to fixes that are missing from your save, compared to a clean save."