A new research report from long-time Apple analyst Brian White (via MacRumors) suggests that Apple will likely announce the 5.8-inch “iPhone 8” at a September event, alongside the two lower-end 4.7-inch and 5.5-inch “S” models, but that the premium model will only be available for pre-orders around that time, with delivery not expected until “several weeks later.” White notes that while the higher-end iPhone would…