On that occasion, lead tracks were installed on the Katamachi side of Kyobashi Station, but they had an effective length of only four cars; consequently, during the period from 1991 until the inauguration of the JR Tozai Line, only four-car trains were used for trains whose terminal station was Kyobashi Station (as most of the rapid trains on the Katamachi Line were four-car trains before the inauguration of the JR Tozai Line, the above didn't cause serious problems).
なお、この時に京橋駅の片町寄りの部分に新たに引き上げ線を設置したが、この引き上げ線は有効長が4両分しか無く、1991年から東西線開業までの京橋始終着となる列車は4両編成に限られていた（東西線開業以前の片町線快速は全区間4両編成で運転される列車が多かったので、さほど問題がなかった）。