ADL application descriptor not found

Trying to launch my AIR project on the emulator, I keep getting

D:\flex_sdk_4.6_Air_3.8\bin\adl.exe -profile extendedMobileDevice -screensize iPhoneRetina -XscreenDPI 326 -XversionPlatform IOS -XscreenDPI326 -extdir C:\Users\xxx\AppData\Local\Temp\IntelliJ_ANE_unzipped D:\Headr\trunk\headr-app\headr-mobile\app\bin-debug-emulator\DevEmuHeadrApplication-app.xml D:\Headr\trunk\headr-app\headr-mobile\app\bin-debug-emulator

[AIR Debug Launcher]: application descriptor not found
[AIR Debug Launcher]: Process finished with exit code 6

I can launch it fine on the device via USB.

Any ideas how I can debug this further?
I'm not sure how/if it relates to IntelliJ either
This broke somewhere along the way when I upgraded to 12.1.4. Perhaps I lost some settings somehow ?:|

Thanks!