Originally Posted by
djkyyc
To me it means there is no positive space and no economy seats available. As CC and others have indicated above, they are selling seats they don't physically have in the economy cabin as they have empty seats in J (J means business class) that they can op-up pax into in the event they don't have the usual number of no shows.
Even if they do have no shows, they're happy to opup someone if they can sell a last minute fare.
Airlines overbook. Everyone knows this.
Therefore, it should be obvious that they sell seats they don't have.
IKK requires positive space. The end. You cannot get this information on EF.