Extract the 'sent to' email address in the header, not the 'delivered to'

Summary

We need to know what email address our customers are utilizing, we have dozen of them.

Content

We have dozen email address our customers can use. We need to understand which ones they are using in a report.  Using the BUI, we can look at the Email Header and see this, I cannot duplicate this extract.

the code I found in the forum, is pulling in the 'delivered to' email address

 

Version

20A

Code Snippet

substr(to_char(threads.mail_hdr),0+instr(to_char(threads.mail_hdr),'To:'),-1+instr(to_char(threads.mail_hdr),'MIME')-instr(to_char(threads.mail_hdr),'To:'))