1. We removed the 1400px limit also for episode artwork (it wasn't in place for chapter artwork or gifs). We still expect square images as that doesn't break podcast apps
2. I noticed that you had your live episode, ended that, and created a new one as a duplicate. It's better for podcast apps to publish the live ended episode, as that is the same episode as the live and have the same GUID (maybe you just did this because the audio processing didn't work)....