OP here: to clarify, this was a domestic flight booked directly with DL from their website as a Skymiles general member w/ no advanced status. The originally booked FC fare was approx $1450 while the exact same itinerary is now quoted as approx $2050. There are presently two FC seats available. But does a cancellation somehow be considered a "modification" to be repriced such that the fee approaches the booked fare(s) differences rather than $200?