The itch download of Terrasavr is a little browser that loads and caches Terrasavr. If you’re using that, you can force a refresh through the menu.
I'm experiencing the same problem you are - all of the available files are from 2020 or 2024 and I can't get freshly made characters to load at all.
(Edit)
After reading through the other comments, I see that Terrasavr+ is not compatible with 1.4.5 and it's the Terrasavr (no plus) for your OS that gives you an EXE that functions as intended after being unzipped. It seems the dates on Itch.io are either not accurate, or referencing something else and ultimately doesn't matter. Hope this helps.