Foliage shadows become black when moving camera quickly

This has only happened once on a Forest Antiquarian (no issue on a different playthrough), but at some point the shadows started becoming extremely dark as I moved around the camera.

It only happened when spinning the view fast, and then the black would quickly balance out to normal lighting, but this would also result in a big FPS dip.

Video settings in screenshots (DLSS is set to Balanced)