Because of the aging of passenger cars as well as the policy, which had been adopted as part of the rationalization of the Japan National Railway, in order to shorten the running distance when using diesel cars and/or electric cars, the 824 train was split into two, namely the 824 train that runs between Shimonoseki Station and Izumoshi Station and the 548 train that runs between Izumoshi Station and Fukuchiyama Station, by JNR's schedule revision implemented on February 1, 1984.
しかし客車の老朽化が進んだことと、国鉄合理化政策の一環として客車列車を気動車・電車化した上で運行距離を短縮する施策が取られるようになったことから、824列車は1984年2月1日国鉄ダイヤ改正で下関駅～出雲市駅間運行の824列車と、出雲市駅～福知山駅間運行の548列車に系統が分割された。