Bounces assigned to incorrect email

When an email bounces an email is updated to be on hold based on the email_id the message was sent to. This email id may have been updated with a correct address in the meantime - so the new address is put on hold. Alternatively the contact may have 2 emails with the same address and a cleaner-upper or a merger may have deleted one. The email_id no longer links to the bounced address so the remaining instances of that address are not put on hold.

I think to fix this it would be necessary to store the actual email address in the civicrm_mailing_event_queue table. This is 'relatively easy' but the schema change sql might run very slowly & this might be a problem for larger sites