4.6.2 builds crash older devices (iPod Touch 3, iPad 1)

I'm in the process of updating an app. It works fine on iOS 8.1.3, but on older devices running 5.1.1 it crashes right at the Unity Splash Screen.

I rolled back to 4.6.1, did a build, it installed and runs perfectly.

Anyone else having a problem with 4.6.2 builds not working on older devices?