e.g. If I have a monthly recurring task that I want rescheduled based on due date (say the first of the month), and on one particular month I want to delay the completion of that task by a couple of days, I would like to be able to adjust the due date of that particular instance without affecting the due date of the overall schedule. i.e. make this month's due date the third of the month, but when it reschedules for next month, it will still be for the first of the month.