JR East have announced that they will develop a new Shinkansen inspection train to be introduced in 2029, which will be called the E927. The new train will be used to inspect all five Shinkansen lines that run north from Tokyo: the Tohoku, Joetsu, Hokuriku, Yamagata, and Akita Shinkansen networks.
The current East-i (E926) inspection train on the left, and an initial design image of the new E927 on the right