Yesterday we began rolling out support for WebSub, which will allow more precise timing for your podcast updates. ~25% of the popular podcast feeds on our service have WebSub support already, and though the protocol has been around a long time it's receiving increasing support in the podcast ecosystem so we'll hopefully continue to see that number go up. Read more about WebSub here and here.
Castro users are already seeing the benefits of more timely notifications. More improvements to come soon!