I am having some of the same issues with corrupted data on PS4 that is now causing it to be useless to play. It started when I updated to version 6 patch. I downloaded the patch which took such a long time (8hrs) but I did not see any issues. I started my game again and all of my saves where corrupted. I tried several fixes to resolve the issue but ultimately had to delete the game off of my PS4. I am able to play version 1.10 with no issues but can't continue playing without installing version 7.20 which also has the same problems. I am posting this as a fair warning to anyone who may have the same issues as me and to notify Ubisoft that until this issue is resolved I will not be playing this game.