no forwarding for RSS feed URLs?

A while ago, I subscribed to a couple O'Reilly RSS feeds. At the time, the URLs were of the form http://www.oreillynet.com/pub/feed/NN. At some point, those URLs started to be forwarded to URLs of the form http://feeds.oreilly.com/oreilly/xxx. And they're still being forwarded; that part's fine. But now, the latter URLs are returning a 404 error.

Apparently, feedburner.com now handles your feeds. Okay, fine, but wouldn't the polite thing be to forward the former URLs to the new URLs? Or if that wasn't possible, couldn't you at least have posted a "please re-subscribe" message to the old feeds a while before disabling them?