Several people will correct me if I am wrong, but even non-refundable tickets can be cancelled for a refund in the first 24 hours (unless the flight is for travel in the next few days).
Yes, true. But if I cancel beyond the 24 hrs I'm stuck with a big DL e-credit. I'm going to use DL miles this time.
Edit: changed my mind and decided to use my 48K pts to offset the FC tix. Had the option to use all or part of my pts.