Could emptying a storage bypass the global "partially loaded trucks" setting?

I currently have a mix of Pickups (20 capacity), Trucks (60 capacity) and Amphibious trucks (80 capacity). I have a unit storage with 45 units in it, which I would like emptied. I clicked the trash button and set export and general priority both to 1, but nothing happened for a while. Then I toggled the "Allow partially loaded trucks" setting to on, and immediately saw the grey bar on the storage that a truck was coming to pick up the materials.

So my hypothesis is that, because emptying 45 units in the storage would require a partial load, with that setting toggled off, this was never going to be emptied.

I think I'd like that trash button to bypass the global setting because, with the trash button pressed, this storage was never going to receive more units, so if the trucks are "waiting for the storage to fill up to a full load", they will wait forever. And it seems a bummer to have to toggle the global setting for this case.

Attached is a screenshot of the storage after I toggled on "Allow partially loaded trucks"