I think lots of local councils are agreeing to more large developments on borders, apart from the obvious green open spaces being attractive - the councils also see an advantage in that only half (or a third if 3 borders) of the traffic issues and local amenities (schools, shops, roads) required fall inside their council area.
e.g. Small council around here is locating a new Traveller site right on the border with massive city council neighbour.
Ah chocolate eggs. Good to see the real meaning of Easter being recognised here.