I've encountered a save bug. I've started a new game (2nd playthrough) and saved; there was a update, and now I cannot save my progress. It does display the save date, but I'm back to where I saved before the update.
So when creating new saves, you are seeing that the new saves are there with a new date and time, but when you load them, it's loading a much earlier save?
I'm wondering if the slots are somehow getting mixed up. Have you tried it with both quicksaves and manual saves? If so, is it happening for both?