I understand that from the AI website you need 90,000 miles for a business class ticket YYZ to DEL. However it does not say if that is a return trip. Does a return trip cost 180,000 miles in business class.

I also understand that one can buy AI miles at the rate of 1 INR per mile is there a maximum you can buy.

I guess it will be to early to speculate the cost in miles of an AI reward ticket on a *A. However if one can buy AI at 1 INR per mile it might make it worth topping up my Flying Returns to fly a *A carrier.