CNN content is stretched

I'm baffled at how many commercials CNN runs advertising CNN films. Here's the latest example:

https://cnnpressroom.blogs.cnn.com/2021/12/22/cnn-films-releases-trailer-premiere-date-poster-art-for-carole-king-james-taylor-broadcast-on-cnn/

Carole King & James Taylor, OK sounds cool. This was announced a few weeks ago and they are just blanketing their channel with an ad for it. All hours of the day, even primetime. How does this make any financial sense? Say it's a two-hour movie, which gives you around a half-hour block of advertising to sell. I watch CNN for an hour here and there and see this add several times. They will have burned up well over a half hour of their own advertising time to sell...their own advertising time?

Am I missing something? They did the same thing with that Princess Diana film.

The only conclusion I can arrive at is that they don't have enough legitimate advertising and content to fill the hour, so instead of dead air we get these meta-ads.