A Reuters report this morning added more weight to the growing chorus of voices who say that Apple will wait until September to ship the next iPhone.

Citing three sources with “direct knowledge of the company’s supply chain,” the news service said that Apple is likely to refresh its iPhone 4 this year, but buck its regular schedule for the iPhone 5.

The report also said the iPhone 5 would not differ much from the iPhone 4. It did not, however, mention the tsunami and earthquake in Japan as a possible reason for delay.

The first rumors that Apple would save the iPhone 5 for a fall debut surfaced late last month, after The Loop confirmed with its sources that there would be no hardware announcements at Apple’s Worldwide Developers Conference in June.

One thing’s for sure: whenever the iPhone 5 debuts, customers will undoubtedly be in line to snap it up. In its first-quarter earnings release, AT&T said that its iPhone activations increased by 1 million over the previous year, despite facing competition from Verizon Wireless.

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