Unless IANA decides to vary its (relatively new) policy on this, .io registrations should stop imminently and the zone will have a maximum of 10 years before being deleted.
@RolandRides .su pre-dates the ccTLD retirement policy so it's kind of grandfathered in. All the other obsolete ccTLDs have been deleted I believe.
@russss I wonder if the cctld can be migrated to a vanity tld while staying connected. We have so many junk TLDs like .cfd that keeping it alive wouldn't be that bad.
@RolandRides I think that would also require a policy change because 2-letter TLDs are reserved for country codes. But apparently they might be considering it in this instance.