Where I live I have an airport 15 kms or so away.

The Runway runs EAST to WEST and the control zone is a big elongated rectangle.

However the geo warning zone shows a huge circle with a lot of what is outside the airport control area been shown as bing inside this area.

This is not correct.

When will DJI adjust the shapes to show the correct information ?

When you inform them that it is incorrect. Contact them and tell them about it.

Its happening everywhere, not just in my area

There does not appear to be a formal way to do this, do you know one ?

For example, just browsing map.

the dotted line is the official one but the circle shows a much larger area.

and near you.

The good news, is that is a green circle.  If it is just a warning zone, it'll just warn you and you can fly no problem.   If it is an enhanced warning zone, you'll need to unlock it, but that can be done without being connected to the internet and while you are in the field no problem.

I think you'll find that they take a point within the location and do a simple circle around it....it isn't any more complicated than that.  Your original post where there is a rectilinear boundary shows this point....they are doing just circles with a radius to bound the flying.

I'm not defending this decision, just stating what they have implemented.

What I would suggest is that you do contact them about, perhaps, enhancing GEO even more so that it more follows the shape of the subject you are being warned about....that could be a great enhancement to the GEO system.

Taken from their GEO page, here is how you contact them:
GEO Page:    http://www.dji.com/flysafe/geo-system
Contact email:   flysafe@dji.com

GEO is an evolving process, in time things will change.