Revisions
When you update a location, type, or job with effective dating, a revision with the new information is created to retain history.
For example, you have a job named Lab Manager that has an effective date of January 1, 2000 and an expiration date of Forever. You update the job to change the name to Lab Manager Floor 2 with an effective date of July 7, 2018 and an expiration date of Forever.
From January 1, 2000 to July 6, 2018, the job name is Lab Manager and from July 7, 2018 until forever (or another update is made) the job name is Lab Manager Floor 2. The job name that is displayed depends on the date selected in the calendar.
Time gaps are allowed between revisions as long as there are no locations attached to the job or type during the gap period.