Deliveries on for a belted item should allow deliveries, not take in more from the belt
Currently, when you enable deliveries on a building that has belted products, it doubles the buffer space, but then fills it from the belt, making it redundant.
It should instead all 'overfilling' by trucks to use rogue product before belted (toggleable?)
This would be great for immigration copper plates especially, but also for cleaning the shipyard of all the boat travels. (default priority 13?)