I think there are actually pictures and pdf's out there somewhere for the T2 extension, Pier B (as above) and T3 Pier extension which also illustrates the changes to the road network.
Some of the Airport City images show the T3 extension if I remember rightly and also a link between T1 and T2 although I've never seen a 'proper' drawing of this.
My view is that we will see the 9,000 space car park lead to the T3 apron expansion car park going then the apron expansion and then the pier expansion hopefully all in quick succession.