In order to know the last time that a changed was done in a job's process, an additional field was added to the jobs' listings: Status Last Changed.
- If the field is not available in your jobs' list, right click the list and press Field Chooser. Add the field to the list by dragging it.
- Create a new job.
- Move it to the next stage.
- Go to the jobs list and check the Status Last Changed field.