yesterday's (15th nov) run of this train from UBL to VSG had an additional coach labelled "RA-15". Half of its windows were sealed glass (2A type) and the other half were regular sleeper class open windows. In those few moments before departure all I could see was the aisle was open (didnt have the cabin door like other AC coaches) and also there was a sofa kept right next to the door. Does anyone know the purpose of this coach?