@Krati_Dixit - Hi there! Several of us Asana users are looking for this same functionality. Feel free to VOTE this up – and get others to vote on it as well 
– here on this Product Feedback forum… Subtasks automating dated backward from due date
@Krati_Dixit - Hi there! Several of us Asana users are looking for this same functionality. Feel free to VOTE this up – and get others to vote on it as well – here on this Product Feedback forum… Subtasks automating dated backward from due date