Cases of iPhone 5 have reportedly appeared in AT&T’s inventory list which fuels expectations that the next generation Apple smartphone could be a more radically revamped iPhone 5, instead of the minor iPhone 4S upgrade.

According to BGR.com, who originally published the leak, the image shows three different models from case manufacturer Case-Mate, which have been loaded into AT&T's inventory, ahead of Apple's Oct. 4 iPhone event.

Speculations concerning the two possible models continue to grow but the almost universal hope is for a next-generation iPhone.

The iPhone 5 is expected to run on the latest iOS 5, which will be coming with 200 new features, including an improved notifications system, a Newsstand and iMessage. In addition to this, the iPhone 5 is expected to feature the new iCloud service in operating iTunes for wireless remote access of music from all computers and mobile devices.

At the same time it could be possible that a cheaper iPhone, armed with significant numbers of features, may be in a position to counter the Android devices that are, at present, inundating the low-to-mid-price market for smartphones.

A Wall Street analyst speculated that Apple could release two phones - the iPhone 5 and a cheaper iPhone 4S - at the upcoming event on Oct. 4.

Specifically, we expect an iPhone 5 with aluminum uni-body construction, better camera and slightly larger screen size as well as a cost-down iPhone 4 or iPhone 4S, Deutsche Bank analyst Chris Whitmore wrote in a note to clients.