Unlikely. The maintainer was pushing updates more frequently and sooner than the original app. it'll be fine
Otherwise, look into cryptomator. A completely different approach, it makes use of your existing cloud storage accounts, but at least more private then using those directly. It probably requires internet access all the time a file is accessed, though, but check the docs to be sure.
It might not be what you're looking for, but I use rsync (the android client is syncopoli). You will have to do some light scripting though (but no other apps involved).
Interesting, I'd heard of the name but never looked into it. Is it better than Syncthing or is that simply what you tried first and have been fine with?