Expected Result: Autosave and Save both save the game and I can continue playing as normal
Steps to Repeat:
1) Load Autosave1, Autosave2, or Autosave3 (attached)
2) Save the Game
OR
3) Wait until Autosave tries to save the game
Result: Current Behavior as described
Description:
I went to bed the night before with the game running, and, when I continued playing the next day, the game crashed on its first autosave. Attempts to manually save after loading the latest 3 autosaves all encountered similar errors.
Seeing other articles, I attempted to clear my saves and change the directory before re-opening them, but the behavior persisted.
It appears that the game save itself may have an issue, but I'm uncertain how the autosaves saved correctly in the first place, then.
Earlier saves from several hours before appear to work correctly, which suggests the error is specific to my latest autosaves. I've uploaded the latest three that all exhibit the same behavior, as well as one from earlier that does not.
Any assistance would be appreciated! I'd rather not lose a whole day's worth of builds, but I can certainly reinforce my defensive line more, too.

(Also, if anyone has any tips about the defensive line, I'd appreciate that, too!)