Hi Fudge,
The following is word for word from my TA.
Dear Sue,
I am also very sad that Silversea had to cancel the voyage, and I would be happy to help arrange a refund back to your credit card, however Silversea is adamant about it being either a full refund, or 20% off another sailing for 2024, they refuse to do both, even though the letter did not say And/Or between the two line offers and is very ambiguous. I have spoken with several offices and all say the same thing. If you find another sailing for this year, I can try to force the issue with them again and as them to book it for you with additional 20% discount from this offer (cannot guarantee the results, but will do my best). Please let me know.