As you can see here, my point light (and others) have a square shape when casting onto this material which is translucent volumetric directional.
This is a moveable light. Not stationary/static/baked.
Any help is much appreciated
Because it’s a static light. Static lights bake all of their lighting down to lightmaps, including the volumetric lightmap which is a sparse grid.
Ah sorry, didn’t notice this was volumetric directional translucency. That’s just how it works, it’s sparse volumetric lighting. You need to use surface foreward if you want lighting with any meaningful detail.