Apple usually holds its iPhone events on the second Tuesday or Wednesday of September. It has been historically doing that, for quite some time. 9to5mac reminds us of the events held on Wednesday, September 12, 2018; Tuesday, September 12, 2017; Wednesday, September 7, 2016; Wednesday, September 9, 2015.
This year, Apple could hold its iPhone 11 event on September 10, as hinted by an image inside the latest iOS 13 beta 7 (below). The image is a placeholder used by Apple for its OOBE (out of the box experience), and iOS 12 contained a similar image with the Calendar showing September 12, which is when the iPhone Xs was announced.
Apple is expected to release three iPhones this year too. However, thanks to some recent chatter, we’re confused about the naming scheme. What appeared to be a natural evolution of the iPhone, with the iPhone 11, iPhone 11 Max and iPhone 11R, now seems uncertain, as reports are popping up mentioning the iPhone Pro moniker.