We need a way to differentiate between sub-accounts when there are 'spam' notifications. We run an agency account, so have 50+ different accounts sending email and it's difficult to know which client account has the issue when we just get a generic message that there is a high spam notification count somewhere. We take great care in following double opt-in rules and if one of our clients does something without our knowledge, we'd like to be able to address is with them immediately.