GLES 3.1 Android not working with new materials?

I recently tried adding a new effect to the UE4 Editor and came across an issue where I couldn’t change my rendering level to Android 3.1.

My material is listed below; I applied it to 3 different objects in the scene, and used a straight Lerp with the background skysphere (BP Skysphere with a texture worldspace material added) and a more gray color to dull it out.

Am I making too many calls to Pixeldepth? Too many instructions? What am I doing wrong here?