DB10 - thank you for all the points you make, but for me they raise a few questions:
I think we are looking at a major extension to an originally fairly large building - probably Victorian in origin. There are so many differences in style as shown in the attached pics that lead me to believe that the original building was a C shape with a large verandah entrance between two wings.
The original building had no timbering at first floor while the presumed "extension" has extensive timbering (Mock Tudor) which might place it as Edwardian. Also the roof lines are totally wrong if this was a one off build.
I think they were changing the frontage to be the large porticoed entrance shown in the top pic which meant creating a more sweeping drive into that facade of he building.
This original building fronted on to a "road" which at that time was unmade but you can see evidence of a road edge running across the original "frontage".
I see what you mean about changing the frontage, but if the original entrance (under the verandah) was facing the road, is it likely that when creating an even grander house they would move the main entrance round the side, where it couldn't be seen from the road?
I also take your point about the mixture of styles, but wasn't there sometimes a tendency (Arts and Crafts movement???) to build things to look as though they'd grown organically over time, even though this wasn't the case?
I don't think it was in "the middle of nowhere" as you can see evidence of a large shadow to the left, which I think can only be another building, and evidence of roof lines to the right.
In the bottom pic you can also see evidence of a pole and cables which are running parallel to the road which would indicate that this is not a remote location.
I'm not sure about the shadow, as I would then expect to see some evidence of the other building in the first picture, which is taken from a bit further away. It would also, I think, mean that the new portico entrance would be facing this other building rather than the road - a bit unlikely?
Thank you for pointing out the other buildings in the distance on the right. The picture I'm now getting is of (possibly) a house on rising ground, perhaps overlooking an estuary or flood plain, with other houses lower down and a rough road leading up to it.
But that still doesn't explain to me why they might move the main entrance to face away from the road - unless perhaps the opposite side of the road was about to be developed and there was still a good outlook to the side.
Further thoughts on this (and your site plan!) would be most welcome.