What does the function Job Updating do in Microsoft Dynamics AX?

There is a function on the jobs form called Job Updating that has prompted many questions about just what the purpose of this function is. You can see it by opening a production or batch order that has been job scheduled, in the Action pane>Production order tab>Production details field group>All Jobs to open the Jobs form and clicking Functions>Job Updating

 

Once this function is run the jobs and job reservations will be cleared from the Jobs form:

Many users thought that this was not correct but actually this is by design.  Job updating should clear the jobs and job reservations.  It is designed to clear a job schedule and apply to the job list any changes to the route on a started production/batch order.  Once this is done you will need to job schedule the order again.

Job updating can be used to make changes, made on the production route, on a started production order effective. For example you have a started production order with 3 operations and the production order is job scheduled and started. The first 2 jobs (operations) are completed and feedback, hours and good quantity are reported via the job card journal. Materials are consumed via the pick list journal. Now you have to start the 3rd job but discover that the work center is occupied by a rush job and you have to choose an alternative work center for the last job. The last operation and workcenter is changed on the production route. After the change, highlight the operation with the change and hit Inquiries/Jobs. This will mark the 3rd job (with the old workcenter). Now hit Functions/Job update and the current job will be updated with the ‘new’ workcenter. Reschedule the Job (or the Production order) choosing an appropriate scheduling direction/method.