Paperless provides an export tool that lets you export all your documents. There’s no guarantee that the import will work on a higher version, but usually it’s fine. Just make sure that you have a clean install without any documents before importing from an old export.

It’s also possible to export all documents and metadata via the REST API, though that’s a bit fiddly. Then you can import them the same way. Again, this should only be done into an empty system, because otherwise your object IDs will be all scrambled up.