Well, honestly, I only use 1 Truckstop per Route, because the AI sometimes use them too and I like to have things “clean” 🙂
And while your description sounds logic, in my case there was only 1 good in the depot… The second ramp was free, but the game always loaded the second good to ramp A, which is taken. So the cargo dissapears.. I should note, that this second good is something I did not plan on, it one of those “hitchacker” goods,where the AI is using the Depot to speed up it’s own traveltime.