Toei Subway Series 6500 trains enter service
https://www.railwaygazette.com/metros/toei-subway-series-6500-trains-enter-service/61691.article
The article says the new trains will run through Meguro Line. But, after full opening of Sotetsu Shin-Yokohama Line, they will also run through Sotetsu Shin-Yokohama Line and Main Line.
But, how often we can see the trains depends on diagram.
