To be honest, I haven’t implemented this yet…. but here’s what I’m thinking about: give them a specific rank. Then, use the rank icon and/or username icon to indicate that account is no longer active. 

The key part will be find a way to position this in your rank documentation without it seeming like a bad thing. But I think it’s a good idea to set the expectation for people that they likely won’t get a response if they send a message or @ that user. 

What I’ve done previously is changed the username to a version of “Community Team” or “(company) Team” and updated their email address to go to a group inbox so that any email notifications (DMs, @ mentions, replies) go somewhere where the existing staff can monitor it. 

Tip: you can add + and then text to the end of an email to create a unique email that still goes to the same inbox. At least that’s possible with emails powered by gmail. So if you have multiple people who have left and you want to have their emails updated to a group inbox or new person you can do something like “emailname+1@domain.com”. What I did is “groupinbox+name of person who left@domain.com”. That way, when I get an email notification to my group inbox, I can see in the email address that it was someone engaging with the account for someone who left. 

(You could also always erase the user, which keeps their post and changes their username to “Anonymous user.” However, I don’t find that to be a good approach for articles and posts by staff who may be giving community or product updates.)

Thanks @DannyPancratz, that’s really helpful! Will give that a go  

I wonder if you could use the custom user title that’s present as part of a user’s profile, instead. This overrides any ranks you may have allotted via the leader board function, and helps to not have to create a separate “rank” for your purpose.

We use this to identify influencers and partners who participate in our Community and allow us to showcase them separately. Seems a bit cleaner in maintaining and cataloguing users (external and/or internal) that way :)

Oooo custom user title is a good recommendation there. 

I would set this up as a role that grants a rank named something like “former staff member”. That way it’s a one-click change for the CM, and the rank can be set up to take care of removal of all of the other permissions that the user may have had, while still keeping their staff status visible for any posts they may have made that still needs that status.