The slot has been upgraded with Extra Robots I, Predictive Stock Control, Heated Wing Mirrors, and Folding Wing Mirrors.
The stockpile has 8(+0) Heated and Folding Wing Mirrors in it, but is also showing 0(+1) paint, specifically undercoat it looks like. My painting operation is nearby but this isn’t it.
I watched it for a while and suddenly, instead of asking for paint, it was asking for +1 rubber.
I am making parts (for example tires) onsite, but nowhere near here.
All models of my cars use heated folding wing mirrors.
I ripped out the slot and replace it and the problem stopped. Only 8 of the 16 stockpile slots will be filled with heated folding wing mirrors. Every once in a while some normal side mirrors show up and then disappear, but I suspect this is WAD.