There’s no minimum or maximum length a branded company podcast needs to fall within. I think more companies should try out the model of repurposing a written content series into a narrated podcast series:

Buzzsprout Weekly

The podcast hosting company already has a weekly email newsletter with podcasting-related news and tips. They’ve now turned that into the equivalent content in podcast form. It’s pretty low lift as the script is already written out, and each episode is short, clocking in at three minutes each for the first three episodes they’ve released. Just think how many branded podcasts there would be if even a small fraction of the companies with email newsletters turned them into podcasts!

https://brandsinaudio.com/podcast/buzzsprout-weekly