Sounds like you missed the library update settings that disable updating manga if there are existing unread chapters, or that you haven't started it.
Honestly looking forward to the Intel options. Their hardware decoders would work great for a remote streaming handheld.
This is what I use on my server.
It has been, I'm subscribed to the issue. But no progress has been made on it for a while.
It sadly doesn't support SFTP. Would switch if it did.
The great thing about this is that you will likely be able to flash SteamOS on it and use it like a Steam Deck. I'm thinking of getting one for that.