Tokyo Metro puzzle special: Oops, the lines are coming down

Here is my first Special Edition puzzle, and it is a little harder.

The map is also available as a PDF.

So you, being a Tokyo straphanger, was in between Hikawadai (Y05 F05) and Kotake-mukaihara (Y06 F06) on the Fukutoshin line when it shut down and all passengers were ordered to disembark. That resulted in a rather large passenger pileup in Kotake-mukaihara. However, you were able to get on the Yurakucho line heading for Shin-kiba. Your planned destination is Nishi-magome (A01). However, the lines are going to shut down, one by one!

Each time you ride by 6 stations, another line will shut down, in this order:

1. Yurakucho line (so get off there quickly!)
2. Marunochi, Namboku , & Mita lines (at the same time)
3. Oedo line
4. Shinjuku, Ginza, & Chiyoda lines
5. Tozai & Hibiya lines
6. Hanzomon line
7. Asakusa line

You have to get there before the Asakusa line shuts down in 42 stations. Good luck!

Clarifications:

1. Changing lines requires 2 stations' time.
• Hello and welcome to this site! I like this puzzle idea very much. – BmyGuest Mar 6 at 8:58
• Can the JR Yamamoto not be ridden? It seems to be the shortest route. – Jerry Mar 6 at 10:10
• Has a correct answer been given? If so, please don't forget to $\color{green}{\checkmark \small\text{Accept}}$ it :) – Rubio Mar 8 at 21:27

I found another way. Start from Kotake-mukaihara riding Yurakucho line (Y06) as specified.

1. Disembark at Ikebukuro (Y09, 3 stations), ride Marunouchi line (M25, 5 stations)
2. Disembark at Otemachi (M18, 12 stations, assuming you can disembark there just before Marunouchi line shuts down), ride Tozai line (T09, 14 stations)
3. Disembark at Nihombashi (T10, 15 stations), ride Asakusa line (A13, 17 stations)
4. Disembark at Nishi-magome (A01, 29 stations), done.

From my understanding,

Yellow line closes after stop 6; red line closes after stop 12; pink line closes after stop 18; and rose line closes after stop 42.

Could you do:

Yellow line to Ikebukuro (3 stops) plus an additional stop to transfer and switch to the Red line (2 stop). Then go to M21 Hongo-sanchome (4 stops) and transfer and switch to the pink line (2 stop). Then go to E11 A17 Kuramae (3 stops) and transfer and switch to the rose line (2 stop). Then go to A1 Nishi-magome (16 stops).

Altogether that seems to take

32 stops, if I've counted correctly.

Is this reasoning correct?

• Great job on answering it so quickly! However, please note that switching lines takes 2 stops; however, I thought it was hard; it was actually easy! – Tzu Li Mar 5 at 2:10
• Updated! Thanks very much, @TzuLi! – El-Guest Mar 5 at 2:21
• @TzuLi Don't underestimate the capabilities of the community here. I've seen puzzles solved in no time which I would consider extremely hard. If a puzzle survives a whole week, it often is either unsolve-able or failed to catch the community's attention for some reason. – BmyGuest Mar 6 at 9:00
• @TzuLi are any of the two answers provided to you worthy of the check mark? – El-Guest Mar 6 at 11:58