Buzzfeed's reliable John Paczkowski recently reported that Apple's annual iPhone event would kick off on September 9. Doing the math...checking calculations with NASA...September 18 should be the iPhone 6S and iPhone 6S Plus' sale date.
The German blog's report is based on sources from Germany's top three wireless carriers, claiming to sell the devices on the same date. Following more Apple history, the new iPhone models should launch first in United States, Canada, United Kingdom, Germany and a few other markets, then a second wave shortly after.