There have been a few entries I've seen that are marked as reposts which suggests that it may be permissible (although to what extent or under what circumastances is unclear to me)…

Mechanically, a bit of experimentation showed no way I could find to link a specific content post to a second jam.

Also being new to the jam thing, I will be interested in seeing what the specifics are….

Multiple posts of the same thing is against the rules, I think it's considered spam ;--;