Except posting here is what admin has asked us to do in previous situations. PMing was literally discouraged. I did end up sending an email.
Edit: Sorry, I realize he directed people in that specific situation to !moderators@lemmy.world, but there have been multiple times in extremely similar situations over the past week when users have been told to post here. Both are modded by the lemmy.world admins, and I would think either is appropriate.
Thanks for the reply! I and my wife are two of those thousands who were helped by that subreddit over the years. I would love to help build a similar space here for those of us who have left Reddit completely behind. My intention was not to stage a coup or hostile takeover -- I just wanted to see it turn into an active and positive community.