It has come to our attention that there are issues and latency for subscribers to any RSS feed (Libsyn and non-Libsyn hosted) in the Apple Podcasts store. This can cause delays in accessing content for new subscribers as well as obtaining new posts from existing subscribers.
We have reached out to Apple Podcasts and are currently waiting a response. We will update this post with new information as it comes across.
UPDATE 10/4/2016 9:13am: Apple Podcasts is aware of the issue and are working to resolve the latency issues. The issue is still ongoing and intermittent.
UPDATE 10/5/2016 12:06pm: Apple Podcasts has continued to investigate intermittent delays, however, the issue seems to have alleviated at this time. If you continue to experience issues subscribing to a show, please contact firstname.lastname@example.org.