Question VFX Submesh Masking (Output Particle URP Lit Mesh Block)

After spending sometime compiling mesh assets with sub meshes, I've hit a bit of a stumbling block that I hope someone has the answer for.

I want to change the submesh mask property (to display a different submesh) randomly by particle. As soon as I try to link up a random mask, I get an editor error:

Can not link a GPU operator to a system wide (CPU) input
Unable to compute CPU expression for mapping : subMeshMask

I get the gist of the error (I can't mix GPU and CPU domains operations), but I'm hoping there is a way of selecting a submesh by particle?

 

So a bit of an update on this that I think works. You can of course call the "Play()" method on a VFX to send play event multiple times (spawning more particles). So, if you wait a frame, then change the submeshmask, I believe the fresh Play() adds additional particles to the output using the selected mask. A bit of kludge but I think it works?

 

same here. I want to change the submesh with prticle id.