Ensure Steam Cloud is enabled, as it can sometimes act as a recovery point for lost progress.
Are you currently trying to , or were you looking for a specific gameplay feature added in that update? Hydroneer Patch Notes - Bridgepour
For the most accurate help with a specific "lost progress" issue, you might want to join the official Hydroneer Discord, where the community often assists in repairing broken save files.
If you are looking for this data because you encountered a or a reset world (common issues linked to update notes from that era), the community and developers suggest several fixes: