As some one mentioned, the booking of all Altis 1.8 variants has finaly stoped, and a Indus motor represtative also said the engine is the ZR,
Discontinuation of the 1.8 Variants makes it quite positive that the ZR engine is coming. As i dont think they would be going for something they discontinued, around 6 years back, but as the 2NZ and 2C are still being used they can go back to 3zz, to increase the profit margin, and maintain prices.