Updating my moved podcast feed — problems remain

I had been hosting my podcast through Squarespace, but I am leaving that service soon so I can have all of my sites running on my own WordPress sites. So I am trying to move my podcast without affecting any listeners. Here’s what I’ve done so far:

— added the iTunes new feed tag to the old podcast feed at Squarespace
— used Squarespace’s URL mapping feature to do a 301 redirect

I’ve had some success: the iTunes feed has indeed updated, and I checked one podcast client on iOS (Castro app) and saw that it works. There are two issues I’d like to correct:

1. In changing the feed, the data of the podcast changed. The title is not formatted correctly, and the byline says “By Unknown,” which I’d like to correct. I have no idea how to go about fixing either.

2. The feed is not updating everywhere. I use Downcast, a fairly popular podcast app, and it’s still pulling from the old feed. Is there something I’ve yet to do that can fix this? I considered simply asking people to update the feed by releasing a short audio note on old podcast feed, but I can’t even search for the new feed in Downcast. It still pulls up the old feed.

Thanks for your help on this. I am not using any plugins for the podcast — just a category feed that only gets the podcast episodes. Here’s the link to the iTunes page if that helps: https://itunes.apple.com/us/podcast/critics-agree-podcast-carroll/id671331919?mt=2

Appreciate your reading! Willing to try any ideas you may have…