I called and spent a LONG time on the phone with Seabourn. First I spoke to a regular reservations rep. She told me, "Sorry, you canceled the cruise before we canceled the cruise altogether, so you are only eligible for a future cruise credit." IMO, this was beyond unreasonable because we canceled on March 9 because of the pandemic - only a mere few days before Seabourn canceled on March 13. I asked to speak to a Lead. The Lead came on and listened politely, but eventually told me the same thing: "you are only entitled to a FCC because you canceled before Seabourn canceled the cruise". I asked the Lead if there was anyone more senior that I should speak to before I escalated this matter. She put me on hold for a long time and eventually came back saying a Reservations Supervisor approved an exception for us: we would receive our entire cruise fare refund by credit card.
[Incidentally, our traveling companions on the cruise also got this exception granted (full cruise refund vs FCC even though they also canceled on March 9).]
It's now June 6: our traveling companions received their refund for port taxes/fees weeks ago (we have not received that refund yet) and we are all still waiting for the cruise fare to be refunded by cc. Repeated calls to Seabourn regarding refund status assure us they are working through the queue...