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About Schedule Horizons and Time Zones

The ABS and Optimizer use the following time periods for scheduling activities:

• Glued period. A time period, starting from today, when you cannot schedule activities. This period prevents changes to schedules and assignments that are already sent to field service engineers. A Glued period is not required. You can set the value to 0.
• Contract Scheduling period. The period of time in days for scheduling immediately pending activities for a specific service region. Typically, this period covers days 2 to 7 (from the end of the Glued period to a week from today).
• Optimizer horizon. A period of time that includes the Contract Scheduling period. The Optimizer operates in this time period.
• ABS horizon. The period of time in days for scheduling future activities extending from the end of the Optimizer horizon to some time in the future. The ABS horizon is the length of time that is available to book appointments for a service region. Typically, this horizon is from day 8 to day 56 (a week from today to 8 weeks from today).

Both the ABS and the Optimizer horizons are represented by a single time line because both horizons are measured from a current time (the time for loading data). For more information, see About Loading and Reloading Data for Service Regions.

Figure 2 shows an example of how you typically define these schedule horizons.

Figure 2. Scheduling Horizons

The Glued period is day 1. The Contract Scheduling period is days 2 to 7. The Optimizer horizon spans the Contract Scheduling period and is also days 2 to 7. The ABS horizon is days 8 to 21, and appointment booking occurs for that period of time.

The schedule horizon is relative to the current day (today). Therefore, as time passes, activities move (from day 1 to 30) along this time line. For example, a service activity might fit the following situation:

• An appointment to perform an activity is scheduled into a time slot some time 8 to 15 days from now. The ABS assigns the activity to an employee during the ABS horizon.
• As time passes, the scheduled activity moves closer to today. On day 8, the activity moves from the ABS horizon to the Optimizer horizon. In the Optimizer horizon, the Optimizer evaluates the schedule, and determines the best time for the service activity and person to complete the service activity. During this processing, the Optimizer tries to minimize the costs of a schedule.
• The activity remains in the Optimizer horizon for 6 days. The Optimizer might adjust the schedule at regular intervals but at least once each day. This schedule adjustment might be necessary because of changes in personnel, emergency service calls, or service activities that contractual commitments regulate (for example, a warranty repair that is required within 12 hours).
• On day 1, the Glued period begins and the schedule for the activities in a service region is locked.

ABS Horizons and Long-Range Appointments

You do not have to use the ABS to schedule activities that are far into the future, such as 6 months ahead. Some companies schedule preventive maintenance activities months ahead of time. The activities are automatically scheduled when they are loaded into the ABS if an ABS horizon exists.

For example, today is March 1st, and the ABS horizon is 14 days. You can set a preventive maintenance activity for May 1st. (Earliest Start is May 1st 9:00 A.M. Latest Start is May 1st 12:00 P.M.) This activity remains unscheduled until April 17th. When the ABS is reloaded that evening, the ABS queries and finds the activity. Because the activity is unscheduled, the ABS attempts to automatically schedule it by using the Earliest Start and Latest Start values.

You might want to use the ABS to schedule long-range appointments when you think that maximum capacity is near, and you are concerned about overbooking.

NOTE:  Longer horizons require more memory. Also, note the 10,000 query limit on activities for each service region.

Time Zones for Schedules

Siebel Field Service stores all times using the UTC (Universal Time Coordinate). To display the local time in the user interface, the UTC is converted to the appropriate local time zone. Service calendars use Universal Time Coordinate conversions. For more information about ongoing application administration tasks, see Siebel Applications Administration Guide. For more information about UTC, see Siebel Global Deployment Guide.

NOTE:  UTC is not the same as GMT (Greenwich Mean Time). UTC does not observe daylight savings time, but GMT observes daylight savings time.

Scheduling uses the following time zones:

• The customer time zone. Appointments are scheduled in the time zone for the customer. The time zone for the customer is the same as the time zone for the service region.
• The service center time zone. Siebel Scheduler ignores the time zone for the service center and uses time zone for the service region.
• The service region time zone. Activities that appear on the Gantt chart of the Dispatch Board are in the time zone for the service region.
• The employee (field service engineer) time zone. Siebel Scheduler ignores the time zone for the employee and uses time zone for the service region.

  NOTE:  You must specify activity times (for example, the earliest start time and latest start time) and exception hours for employees in the service region time zone. If the dispatcher or service administrator is in a different time zone, then that person must manually convert the activity times and the exception hours for employees to the service region time zone. If that person is in the same time zone, then no manual conversion is necessary.