Speaking to suppliers “related” to the iPhone’s production in Asia, Digitimes reports today Apple still hasn’t released a roadmap for the next-generation iPhone – unofficially dubbed iPhone 5 until today – leading many to believe Apple might want to focus the upcoming WWDC in June (the usual stage for new iPhone announcements) on software and release a new model this Fall, or in early 2012. Digitimes, however, also reports another “theory” that has been formulated by component suppliers: unlike previous rumors that suggested the iPhone 5 would be a completely new device, the iPhone 5 could be a slight redesign of the current iPhone 4 and still launch this summer “to fend off the rising popularity of Android.”

Apple has not yet released a production roadmap for iPhone 5 as shipment volumes of iPhone 4 have continued to mount and related suppliers are not yet ready to shift their production lines for new products, according to sources at Taiwan-based touch panel makers.

While acknowledging there should be a roadmap for each generation of products, the sources insisted that touch panel shipments for iPhone 4 have remained steady, and that they have not seen a timetable to stop current production in preparation for the next-generation of iPhone.

A report surfaced yesterday indicated the iPhone 5’s production is set to start in September for a Fall release, with a cheaper iPhone model still in the works to grant Apple a larger share in different market segments. According to previous speculation, the iPhone 5 should be an updated version of the iPhone 4 (featuring the same design scheme), but with a metal back and redesigned antenna, 8 MP camera, NFC capabilities and Apple A5 processor.