Although the Bureau wanted to operate rapid trains on the outer track during rush hours, it was difficult due to the relationship with fright trains and superior trains as well as the structure of Ashiya and Takatsuki stations.
ラッシュ時には外側線に快速電車を運転したかったのだが、貨物や優等列車などの列車密度の関係と、芦屋や高槻駅の駅構造の問題があった。