compreface-core only using 1st GPU

Hi ! For some reason, whenever I start compreface, no matter the values of uwsgi_processes and uwsgi_threads, the processes are all started on the first available GPU. I've started it by passing a specific device id in the docker-compose.yml and I can indeed choose which GPU to run, but after that, that's it, I can only roll with one.
Is there anything I'm doing wrong ?

I'm running 1.2.0 with Mobilenet-gpu's custom build, all values are unchanged except for SAVE_IMAGES_TO_DB (false), UWSGI_PROCESSES (2) and UWSGI_THREADS (2)

Thanks !