… and for which UUIDs are sortable. OP called them "not sortable", which is a poor phrasing, as they're sortable. What he's likely getting at is that they're n

… and for which UUIDs are sortable. OP called them "not sortable", which is a poor phrasing, as they're sortable. What he's likely getting at is that they're not ordered by generation time, which matters to some folks.