If a mailer wants to send advance notice to a recipient that {HEAD ~ a mailpiece} has been sent to {TAIL ~ the recipient}, the mailer can choose this option automatically and use a unique mailpiece ID as an identifier of the upcoming mailpiece.  
sent to
If a mailer wants to send advance notice to a recipient that { HEAD ~ a mailpiece } has been sent to { TAIL ~ the recipient } , the mailer can choose this option automatically and use a unique mailpiece ID as an identifier of the upcoming mailpiece .
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH