"Be sure to remove those old BAL luggage tags, or you will have to retrieve your bags in Turkey."

You're right about that, man. Interestingly, it was in 1973 that Baltimore (BAL) changed its name to Baltimore-Washington (which I thought was a bit of a stretch -- kinda like O'Hare changing its name to Chicago-Milwaukee, with Milwaukee already having its own airport) but after the name change, the IATA code remained BAL until 1980; the BWI code had previously been used by an airport in Bewani, Papua New Guinea.