Ok, thanks Laurent,
Nothing to do with download time, everything is up and running for weeks now.
It’s very strange : picking up some very old notes (imported from evernote), I find existing attachments …
So, if I first try to re-import all evernote notes in my existing collection to check if the issue is related to import (or original exported enex files), I’ll have a mess of “first importation” ones and “second try” … that’s not really what I want !
Is there a way to, in my actual joplin collection, delete all notes older than $date before re importing enex ?