On relatively good information I offer the following...
The ancillery endorsement, "Forwarding service requested" may be obsolete for "bound printed matter" mail. Check with your local post office because your mail piece may not be forwardable and may be treated as waste.
Ralph, check this out also as the envelopes may need to be reprinted.
Presorted bound printed matter may have an exception as being forwardable, check with your USPO.