Shadow/AO flickering when rendering

I keep getting strange flickering only when I render (it does not appear in the scene viewer, in Cinematic quality) - in this example you see it between the trees on the right.

https://f.io/Ym9dAooO

It seems to be related to the directional light, or possibly the exponential height fog. If I turn off either the flickering goes away. I’ve tried various changes to their settings but no luck so far.

Any ideas would be appreciated – thanks

Hello!
If you use lumen, a temporary solution would be to use DLSS from nvidia.
I have the same problem and I haven’t been able to find a solution for it