They aren’t connected except that the same mods run them. We don’t, or haven’t so far, posted duplicate posts. So that shouldn’t be an issue.
And then we’re also paying attention and when it seems appropriate, we will likely close down one and redirect traffic to the one we keep up.
Much like I ignored reddit usernames in the comment section, I tend to ignore which instance a post is coming from while scrolling. So I subscribe to all the relevant ones, and just scroll from my “subscribed” in my instance.