Has there been an end date established for the Maps app on iOS less than iOS 6? It has been reported that the contract between Google and Apple to supply maps for iOS has not been renewed (or perhaps already has or is about to expire). Furthermore, it's clear that Google charges significant amounts of money for businesses like Apple to use the maps API so it's not clear to me that this data feed can continue to older OS indefinitely.

Has anyone seen a credible announcement if and/or when the map data might stop working for people that choose to stuck with iOS 3, 4 and/or 5 and the Google-data-fed integrated iOS mapping app? (And by choose, I mean the devices are not even supported on iOS 6 so the choice is more to buy new hardware or keep running what you have.)

I'm not looking for an alternative (like running Google Maps on iOS 5.1) - just an announced or a real end date of the map tile feed to iOS.
As long as you do not upgrade to iOS 6, you will get to keep the app forever. As for the API not working any more, since Apple used the official API any changes Google makes that would break the old Maps app will also break millions of other apps on many platforms. There is a possibility that Google could revoke Apple's API key, but I seriously doubt that will ever happen.