My position was that the domains would continue to exist, because the IANA "is not in the business of deciding what is and what is not a country, nor what code letters are appropriate for a particular country" (from here), and used .su (Soviet Union), .yu (Yugoslavia), and .mk (Former Yugoslav Republic of Macedonia) as examples.
Some disagreed, but could not come up with any examples of a discontinued ccTLD. Can any of you think of a ccTLD which no longer exists? (Here I'm defining "exists" as "has records on the root nameservers". If it's still there but doesn't accept new registrations, it still exists.)