Anyone noticed that some industries have a phantom supply to them, and produce goods from nothing?
In my current map I have at least 2 oil refineries that are at 25/25 production, even though I am not supplying any oil to those refineries. I have connected up lines to those refineries and can provide goods to towns from those refineries.
If industries are close enough, just like people with cars, they transport their own goods/materials… if you cut a road, they stop.
If they’re supplying their own oil, good – it’ll give you a head start when you try to move it – get your rail line set up (road MAY not work, but you can try) and cut the road to the nearest oil supply (you might try grouping two cargo stations together and trying to put the oil one as far away as possible so the refinery cannot use it for getting supplies). With 25/25 already, you should see an initial dropoff, as usual, but it’ll soon build up again, hopefully. If not, just reattach the road.
Or, if there’s no nearby oil, it could be a bug, as you say. 🙂