Have you faked that lower sky, as it seems to have lost its brightness?
Or maybe it's the government's sun-dimming experiments.

No. The sky came out, if anything, too blue, so I desaturated and lightened the whole sky area to look more natural.

The only Sheppertonisation here was the removal of four parked cars, two estate agents' signs and a distant TV aerial and the shortening of the chimney stack, top right, to lower the skyline as far as possible.

Ah, that will explain why it doesn't look natural.