How do I change my podcast description on iTunes from Soundcloud?

The 'Description' text for the overall podcast in the iTunes Store page is drawn from the 'itunes:summary' tag. As you don't have one the Store and the iTunes application are using the 'description' tag. The text currently in that tag in the feed is what is showing when subscribing in the iTunes application (which reads the feed directly) but the Store is showing a different wording.

The Store caches feeds and checks them for new episodes in some sort of rotation. New episodes usually appear in 1-2 days, but changes to the wording may not appear until a new episode has been posted, though the Store may indeed update in a couple of days or so.

You don't say when you made the change, but since it's showing in the application it's just a question of waiting for the Store to catch up. Your last episode was posted in April, and with a long gap between episodes the Store may be slower to get round to checking the feed.

When you have a question please always post the URLs of your iTunes Store page and the feed, to save detective work finding them; and it's best to post in the Producing Podcasts forum.

I have a similar question: I needed to make some changes to my podcast on iTunes through Soundcloud as well. Episodes were out of order, and I forgot to add descriptions to the podcast as well as episodes. I deleted the three episodes I had uploaded from Soundcloud, reuploaded them, and gave them the correct stats. When will those changes show up on iTunes?

Subscribers will see changes pretty well immediately, so you can check by subscribing in iTunes (from the 'file' menu or from the link on the Store page). The Store usually takes 1-2 days to catch up. It's possible that it may not recognize that there are changes in the feed until you upload a new episode.