Hi, Sorry, missed this reply.
We'd usually sort them based on the email address these were delivered to.
Prior to 1.17 (we were running 1.14/1.15 and tested 1.16), these would just show up in the proper topic based on the email address these were delivered to. This is the default behavior and we were able to run with this very well.
Since 1.17 though, yes you are correct -we are no longer able to sort through BCC'd emails and these must be done manually and compared to their individual Office365 mailbox since they are all dumped into our 'default topic'.
These kinds of emails are getting more frequent, for example customers announcing to all their related entities about some new policy changes but do not want to show the names/email addresses of all these entities - hence these are done via BCC.
We could provide some logs or examples if necessary. Thank you! 🙂