This is a big bug that I want Apple to fix, which got worse with the latest update. If you start playing a podcast before it has fully downloaded over WiFi, then move out of the WiFi range and into 3G/4G it will just stop playing.
What it should do is continue the entire download while it is playing, but it seems like it's just streaming over WiFi, then stops because of the 20MB limit. With the latest update iTunes basically just stops downloading anything now if you play a podcast that hasn't fully downloaded yet.
What it should do is continue the entire download while it is playing, but it seems like it's just streaming over WiFi, then stops because of the 20MB limit. With the latest update iTunes basically just stops downloading anything now if you play a podcast that hasn't fully downloaded yet.