3:2 aspect ratio and the Simplified Screenshot Submission Process

According to this recent announcement, a newer and simplified process for screenshot submission was introduced in itunes connect.

Now we can submit screenshots corresponding to the resolution of the largest devices in a family (for iPhones it is 5.5 inch) and they will be used for other devices (4.7 inch, 4 inch and 3.5 inch) by itunes connect with simply checking a box.

I can understand how 5.5 inch screenshots be used for 4.7 and 4 inch devices considering they all have 16:9 aspect ratio. But I can’t seem wrap my head around how the screenshot gets generated for the 3:2 aspect ratio (iPhone 4/4s) from 16:9 aspect ratio.

Is anything special required to be done for iPhone 4/4s screenshots?