Back of a SF Card

Have you looked closely at the back of the prepaid subway card (SF Card) for Tokyo subway? It prints out each journey, with month, date, from and to station, and money left. Interesting points are: the month is coded using a letter. X = Oct. Stations are only 4 kanji wide, at last so far on this card. There are stations that are 5 Kanji wide. What will happen? Makes me want to get off at one of those stations just to see. When can't someone host a scanvenger type game, to see who can collect a full set of station names for a fixed set of subway line, on one ticket?