Hi all
I recently published a handful of open source scripts which can migrate RimWorld saves from A16 to A17, and from A15 to A16. They manage all the complexities of the body part changes in the latest release.
They can be downloaded here: https://github.com/afit/rimworld-save-migrator
I hope they're helpful. I didn't want to start my game again, and you might not want to, either.