SOLVED: Advanced bounce rules: difference between blacklist a user vs. an email address

Can anyone explain the advanced bounce rule difference between blacklisting a user, and blacklisting an email address?
I was looking through the code, and it’s not clear to me what’s done and where…
Is there a ‘do not send list’? I don’t see one, just a table containing blacklisted email addresses.

In the end, I’d like to generate a list of all blacklisted email addresses (from phplist) that I can ‘back annotate’ to an external database. Right now I am using two selects… but it seems to be missing some of the blacklisted contacts…

INSERT INTO external_schema.table (email)
  FROM phpList_schema.phplist_user_user WHERE 
phpList_schema.phplist_user_user.blacklisted = 1 ;
 INSERT INTO external_schema.table (email)
  FROM phpList_schema.phplist_user_blacklist;

(step 1) It looks like when an email address is blacklisted, the email address is inserted into the phplist_user_blacklist.

When a user is blacklisted, the rule marks the phplist_user_user record as blacklisted (=1), and then blacklists the associated email address (step 1).