IF the deal is really for 11 billion dollars, then it will not just be 12 batteries, considering each battery costs 500 million.
It will involve TOT..with further batteries being manufactured in India.
But even if it is just 12 batteries ..then forming a SAM wall(let say ) 100 Km from Pakistan border would serve both the purposes.
Any aircraft or missile launched from Pakistan will have to eventually cross those SAM sites ..to hit the targets inland...So airbases and high value targets inland are automatically protected.
But In case India decides deploy 3 out 4 regiments to protect high value metropolitan cities.
Even if single regiment deployed in Punjab. then it would neutralise six of Pakistan ten main airbases of
Sargodha
Shorkot
Peshawar
Mianwali
Kamra
Rawalpindi