Apple's earnings guidance may have provided us a clue about when the iPhone 6 is coming.
Apple said revenue for this quarter would be $37-$40 billion. This number suggests a late September iPhone launch - perhaps September 26.
Steven Milunovich at UBS breaks it all down in a research note. He's mostly just doing guesswork, but it's educated guesswork. Here's complicated chart with all the numbers:
UBS
UBS seems to be pretty in line with other estimations of the iPhone 6 arrival.
9to5 Mac's Mark Gurman expects to see the phone in mid-September, likely the second or third week of the month.
This also seems to fit with Apple's past releases. In 2013, they unveiled the 5s and 5c on Sept. 10. And they released the iPhone 5 on Sept. 12 in 2012.