Indigo just signed a deal for 430 aircraft from Airbus. All from the 320 series (some 320's, some 321's). Chinese airlines have bought up at least 190 (worth about $27b).
https://www.cnbc.com/amp/2017/12/29...of-the-biggest-aviation-deals-in-history.html
https://www.cnbc.com/amp/2017/12/29...of-the-biggest-aviation-deals-in-history.html