Weird VR thing with hardware encoding (M1)

Since updating to the new AME (v22 build 107) Im getting a weird thing where Ive got some square quicktime videos (1080x1080), I run them through AME to encode as match source, high bitrate. Hardware encode on (I'm on a Mac Mini M1). The 'video is VR' checkbox is definitely not checked, but people using VLC are seeing these finished H264s as VR. And when I upload to vimeo, same thing. 

Weird.