Dark spots in paint.

Try washing with Dawn dish soap, that cuts tree sap.

Kind of looks like Blueberry stains from bird droppings.

Could try a thin mix of distilled water and auto body rubbing compound in a unnoticeable area to see if some of that will clean up, with a cotton cloth by hand.

That single stage paint does not have much clear mixed in, and it is easy to get down into the metallic layers if you are not careful, so be careful and proceed after doing test areas.

Could be animal blood stains from someone hitting a bird. Looks like some type of surface contamination that has soaked in.

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