As a team lead - we have an agreement with client that any incoming email from them will be responded with in 1 working day, so can we have a new due date flavour where from the time the new information is received - my due date should start calculating.

If it is used in a ticket - then new due date has to be given

If it is used at action - then new due date has to be given to action and also to case

If used at case - then new due date for a case has to be changed (usually during a feedback window)