0.8.2c (b559)
This save should open right on one of the assigned refuel station trucks going on a refuel job to the copper mining tower. Should be exclusive to the assigned coal mining tower only. This station's refuel trucks were also servicing tree harvesters and other mining towers.
I've since found at least two other reports related to this. Seems the issue may be that the other mining towers do not have any other refuel stations that can service them. In this case though, this is exactly what I want to happen since there's a nearby standalone diesel storage by these other mining operations from the early game. I had intended that excavators in these more remote / less busy mining operations (such as the copper mine that this refuel station is about to service) would travel the short distance to get their own fuel from the nearby diesel storages. I do not want to build refuel stations in these locations and spare trucks.
I don't think this should be intended behavior, though if that's the case, the export route tooltip should be changed to let the player know of this exception. Or perhaps export rules should be removed for the refuel station entirely. In my case, unless every other mining operation had their own assigned refuel station , the export rule is essentially useless anyway. Another workaround would be for me to rebuild my generic unassigned fuel station (which is what I wound up doing an hour later) but having refuel trucks drive accross the map when there's closer diesel storages was another aspect I was trying to avoid. That's a lot just to get an export rule to be respected. So would introducing logistics zones and more dedicated export routes to support them.

Quick ping @Captain Matt since we were both typing at the same time.