The official website and Twitter account for the anime Kimetsu no Yaiba: Mugen Ressha-hen ( Demon Slayer: Kimetsu no Yaiba Mugen Train Arc ) announced on Tuesday that the broadcast scheduled for October 31 will be delayed by one week due to election coverage for the Japanese House of Representatives.

選挙特番「Live選挙サンデー」放送に伴い全国フジテレビ系列での10月31日（日）の『テレビアニメ「鬼滅の刃」無限列車編』は放送休止となります。
第四話は11月7日（日）に放送いたします。

また第四話のそのほかの放送局・配信に関してはこちらをご確認下さい。https://t.co/oC9tsCC8Ka#鬼滅の刃

— 鬼滅の刃公式 (@kimetsu_off) October 19, 2021

Thus, Fuji TV will air the fourth episode on November 7. All other broadcasts of the series will also run late by one week, as well as streaming.

However, this suspension does not change the release date of Kimetsu no Yaiba: Yuukaku-hen, set to premiere on December 5 in Japan.

Mugen Train Arc premiered on October 10 will feature a re-edited six episodes with new background music, as well as a never-before-seen Episode 1 featuring Kyojuro Rengoku taking on a new mission on the way to the Mugen Train, for a total of seven episodes.

On the other hand, the Entertainment District Arc will feature Tanjiro and his comrades on a brand new mission within the Yoshiwara Entertainment District, where they face the demon Daki (Upper Six).

A new 1-hour special episode will begin this section of the story after the conclusion of Demon Slayer: Kimetsu no Yaiba Mugen Train Arc.

Source: Official website via ANN