Send Elon first

Not really familiar with Synology, but you could build and run it as a docker container. https://learn.microsoft.com/en-us/dotnet/core/docker/build-container

I haven’t personally tried it, but I’ve seen this tool mentioned before: Lemmy Account Settings Instance Migrator

Reddit will sure be a lovely site in a few months…

I use calibre and calibre-web. I have the DeDRM and ACSM plug-ins installed in calibre so I can buy a book from ebooks.com or wherever, drop the acsm file in my auto import folder, then just download the drm stripped epub from calibre-web and import to the Books app on my iPad.