Not if the prisoners have no access to the delivery area...

I have extra cooks and workmen and all access to the delivery area is through guarded, staff only airlocks.
My issue is that when the workmen pick up the plates and head for the workshop, they are still holding the "truck unloading" flag (or something along those lines)...
No new workmen get assigned to unload the next truck so things quickly stack up.
I have not tested the new "place delivery area anywhere" setup yet. I think placing it just inside the airlock will keep the workmen much closer to the trucks so they will end up unloading much faster. Then the prisoners can take the supplies the rest of the way to the shops.
But I still think that more than 6 workmen should be able to unload trucks at once...