Apple is rumored to be sticking to a September or October 2012 release cycle for the iPhone 5 -- or whatever they end up calling the next-generation iPhone -- just as they did with the iPhone 4S in 2011. Japanese news site Macotakara reports:
According to Asian reliable source, the next iPhone will be released in September or October, and this cycle seems to be kept for years.
Previous to the iPhone 4S, Apple historically held to a summer release cycle, with the original iPhone hitting on June 29th, 2007. Subsequent releases of the iPhone 3G and iPhone 3GS were in mid July and late June respectively, with the iPhone 4 following up on June 24 of 2010.
With the iPhone 4S, however, Apple switched to a to an October release window, moving away from the summer cycle they've been accustomed to and taking the Holiday spot previously reserved for the iPod. Given that Apple announced a record-breaking quarter with over 37 million iPhones sold after the iPhone 4S hit consumers late last year, it was likely a smart move and it makes sense for Apple to continue on this path going forward.