Locations and gathered resources reset

[jonesing]

I came back to a save after a month of not playing, and all of my locations outside of my current map (timber wolf mountain) were reset. I had stored up resources and tools across Pleasant Valley, and when I returned they were all empty and "unstarched." Each location showed "new location discovered." Please let me know how to proceed. I did not open this save during the "4 Days of Night," and the issue started and has continued after "4 Days of Night" concluded.

 

MacBook Pro

Intel i7 2.2 GHz

16 GB Ram

AMD Radeon HD 6750M 1024 MB

Intel HD Graphics 3000 512 MB