I printed out a DC (only) label for a book that I soon had to cancel when I discovered a condition issue before wrapping. 

I PMed the receiver and offered to send her the book for free if she wanted to order another from my shelf (as my slightly damaged one was the only one in the system).  She took me up on my offer and ordered another.  I'm wondering if I can use the DC label I printed for the canceled book on the new order as it's the same person/address. 

The system is set up to let you reprint the DC label.  I know I've added books and reprinted the label.  So why not?

I would recommend in the future to add another book before canceling the first one. 

Yes, you can, since you are sending to the same address.  The server won't know about the old label, though.  You'll have to hit "print wrapper" for the new transaction and then fake print a non-DC wrapper for it.  (Don't hit the final button to send it to your printer.)  The server won't let you mark the new transaction mailed unless it thinks you've printed the wrapper.

You won't get quick credit, but if the book goes lost, you can contact the PBS Team.  As long as your sending record is good, they'll likely honor the lost book credit insurance.

If the wrapper included postage, you'd have to get the Post Office to slap on a zero postage meter strip to correct the date, if the date no longer applied.  But I don't think the DC wrapper includes a mailing date.

ETA: Oops, Emily and I were typing at the same time

I agree I should have waited to see what the requestor wanted before canceling.

Thanks both for the advice!