From the start of the 1 December 1996 timetable revision, all of the Musashino Line 103 series sets were lengthened from six to eight cars.
Sejak dimulainya revisi grafik perjalanan kereta api pada 1 Desember 1996, seluruh set 103 series milik Jalur Musashino diperpanjang menjadi 8 kereta.