"If you look at Starscream, the angle at which it slants up from his chest towards the intake is steeper, ending just above his "ear muffs". And there are 4 rectangles above the top of the slope. On Skywarp the slope ends below his "ear muffs" and there are 5 rectangles above the top of the slope instead of four."
That is not where the mystery ends. Our own Cyclonus_3009 brought something to Seibertron's attention. It appears that the Classics Starscream released with Classics wave two share the same remold as Skywarp. Seibertron discovered the proof when he preformed a head swap with Skywarp and a Starscream. Here are some images that show the change in the mold:
Skywarp

Wave 1 Starscream

Wave 2 Starscream (after custom head swap)

Wave 2 Starscream and Skywarp (after custom head swap)

Wave 2 Starscream with Wave 1 Starscream (after custom head swap)
