If you take a look at the 1st page of the 6-green pages (4-pages of the instruction and 2-pages of the ballot), it says, "... IF YOU RECEIVED A RETURN ENVELOPE, YOUR COMPLETED BALLOT MUST BE SENT TO YOUR NOMINEE SO THAT THE MASTER BALLOT CAST ON YOUR BEHALF IS ...". I think we are sending our ballots to our nominee, PROXY SERVICES, which is the addressee shown on the envelope. PROXY SERVICES will collect our ballots, and it will then send the master ballot cast to the Securities Voting Agent. That is the way I understood.
LONGs, please correct me if I am wrong.