[exim] Slowing Blacklisted Authenticated Users

I have this to block users that authenticate and are on a blacklist.

deny
dnslists = some.black.list.or.another
        authenticated = *
        verify=recipient
        message = blocked authenticated sender

Rather then block these I would like to rate limit black listed
authenticated senders to 5 messages an hour or so in case its a false
positve.

I see this:

# Keep authenticated users under control
warn ratelimit = 100 / 1h / strict / $authenticated_id
         delay     = ${eval: ${sg{$sender_rate}{[.].*}{}} -
$sender_rate_limit }s

But how do I make this only trigger on blacklisted authenticated users?