After Effects / Media Encoder not using AMD GPU

Finding that when I try to render a H.264 MP4 or a WebM file and export to Media encoder that I'm seeing HUGE spikes in CPU by After Effects but no utilization on my GPU. I have the encoder in AE and AME set to Mercury Playback Enginer GPU Acceleration (OpenCL) but it's still rendering on CPU (Which while the Ryzen series are great at handling multitasking it still means a 1 minute render can take an eta of 1-8 HOURS versus what used to be minutes.)

I know this worked before because I'm re rendering a project from a few months back that took a bit but not nearly this long!

Thoughts?