Calculation of the Next Due Date in a PM

The Next Due Date in a PM Schedule is the date on which you need to start executing the PM WO. If you select the checkbox “Use Last Work Order's Start Date to Calculate Next Due Date” the Next Due Date for a PM is calculated by MAXIMO based on frequency and first start date, and is a read-only field. If you want to postpone or pre-pone a certain PM task because of any reason, you can do so by entering the new date in the extended date field. In this case, MAXIMO will ignore the date in the Next Due Date field and will consider the value in Extended Date field as Next Due Date. After MAXIMO creates the WO based on Extended Date, the extended date field will become clear and next due date will be populated based on the frequency.
Similarly if the checkbox “Use Last Work Order's Start Date to Calculate Next Due Date” is unchecked the completion date of the last PM work order is used to calculate the next due date.

Courtesy: An old compilation from Infy Team