The discussion revolves around manually migrating S3 uploads to a local server in Discourse. Yt.w asks for guidance since the rake uploads:migrate_from_s3 command is no longer usable. pfaffman suggests creating a backup, restoring it on a fresh server with S3 settings disabled, and using rsync for migration, referencing relevant documentation. kuaza proposes a future enhancement: a single command to switch between S3 and local storage, highlighting its potential usefulness.
Then make a backup. Then restore it. I recommend restoring it on a fresh server. You can use your existing yml file, but delete USE_S3, the upload bucket and the stuff that uploads assets to S3.
I believe this could be accomplished with a single line of code. Adding it to the roadmap might be a good idea. It should be possible to switch between local to S3 and S3 to local with ease using just one line of code. I understand you are quite busy, but I think it could be beneficial in the future if you add it to the list.