Barclays Capital said it has received many questions over the past week around thoughts on the potential timing of Apple Inc.'s iPhone 5.

While Apple has typically announced its latest iPhone at Worldwide Developers Conference in June and launched a few weeks after, we continue to believe this year’s iPhone launch is likely to be later towards the August/September timeframe, said Ben Reitzes, an analyst at Barclays Capital.

Reitzes said usually by now designs for next generation iPhones have been finalized within the supply chain and partners are gearing up for production. To date, Reitzes has not been able to nail down the similar details for iPhone 5, which typically begin to be realized about 4 months prior to launch.

Apple has been historically very methodical with it’s once a year iPod launch (September), once a year iPad launch (January/February) and once a year iPhone announcement (June) and Reitzes doesn't expect the company to skip a product cycle this year either.

In summary, Reitzes believes it may make sense for Apple to launch this version of the iPhone a little later than usual for five reasons.

* Reitzes believes that the iPhone 4 is doing quite well -- and could be poised for more partners in China, including China Telecom. Furthermore, white iPhone 4 models aren’t even out yet and Apple still has to fulfill pent-up demand in terms of channel inventory overall.

While sales through Verizon may lack upside to investors original high expectations, Reitzes believes sales are strong elsewhere (Verizon’s upgrade pricing availability was arguably more limited in scope).

* Reitzes said Apple may need more time to make sure that its product is ready for 4G with certain parts and specifications, in order to be more competitive over the long-term.

* Reitzes believes that Apple’s iPhone 5 may be more effective in tandem with the launch of a digital locker service through MobileMe (using the new data center in North Carolina). This service may be better suited for 4G networks over time.

* The market for near-field communications could be developing at a certain pace -- and a later launch may help Apple work with the necessary partners to include this chip in the iPhone 5 as a digital wallet.

* And finally, given potential supply chain ramifications from Japan -- it may be a good idea to have more time for launch. For example, Sony may now have some manufacturing issues with regard to its 8 megapixel cameras. Given this potential issue and others within the supply chain, it may make sense to wait.

While the later timing could impact analyst estimates from a quarterly perspective, Reitzes does not expect timing to disrupt shipment totals over the longer term.

Reitzes currently expects iPhone unit sales of 15.6 million for calendar first quarter, 70 million for fiscal 2011 and 87 million for fiscal 2012 which could prove conservative given strong demand and the potential addition of other carriers over time.

We believe that potential supply disruptions out of Japan could possibly impact June quarter iPhone sales but we believe that Apple has the potential to catch up later this year. Apple’s WWDC (June 6-10, 2011) at the Moscone West in San Francisco is expected to focus WWDC on iOS and Mac OS X Lion, said Reitzes.