There are also reports of TV broadcasts being shutdown only 20 minutes after the cartoon had ended in 1939. But it did restart with the cartoon again in 1945.

I found this information interesting because no one never really talks about TV during WWII. There were very few broadcasts during the 6 year war as TV was recent and it was considered a niche. Most people got their information from theaters, before the feature filme there would be a small documentary (some of them are stored in British Pathé's account on Youtube)

The Army preferred to reutilize the TV radio signals to use them as a way to disarm potential enemy bombers of their explosive load, before they could reach British borders.

Broadcast shutdown on 1 September 1939, resumed later at 29 July 1945. -- during which BBC and most other networks would focus on radio as their mainstream method of informing the masses.