text: Chapter 6
  * Jam enemy command nets to slow the enemy's reaction to a withdrawal once it is under way.
  * Use deep fires to relieve pressure on units in contact.
  * Provide FPF when necessary.
  * Be prepared to support a delay.
  Planning for Retrograde Operations
  6-58. A defensive situation may require the HQ staff to plan for retrograde operations in combination,
  sequentially, or subsequent to the defensive mission. Planning and rehearsing a rearward passage of lines of
  security forces forward of the MBA is critical to ensuring proper execution while under enemy pressure. The
  complexity and fluidity of retrograde operations and the need to synchronize the entire operation dictate the
  need for detailed, centralized planning and coordination with decentralized execution. A retrograde may be
  forced or voluntary. In either event, a higher echelon commander must approve it.
  FIRE SUPPORT CONSIDERATIONS FOR SUSTAINMENT IN DEFENSIVE OPERATIONS
  6-59. Sustained combat in defensive operations will normally generate the largest requirement for supplies
  and services, stress resupply capabilities for fuel and ammunition, and require rapid evacuation of wounded
  and equipment repair as far forward as possible. Sustainment for artillery units in a defensive role requires
  prepositioning of ammunition and other essential supplies. During a delay operation, supplies should be
  prepositioned at subsequent delay lines or positions. Petroleum, oil, lubricants, and ammunition stocks must
  also be adequate to support decisive defensive actions.
  6-60. As operations shift towards the defense, FS sustainment elements should begin to minimize the amount
  of support forward in the defense. Sustainment staffs will be primarily concerned with providing needed
  support to firing units engaged in corps-level operations and to divisions in whose area the main enemy effort
  is expected.
  6-61. FS and sustainment planners in the defense should consider ammunition and fuel availability while
  maximizing organic haul capability and minimizing requirements for resupply. They should preposition
  additional ammunition and fuel in planned and coordinated cache sites in convenient locations along
  anticipated routes of withdrawal while making plans to destroy these stocks, if necessary.
  THE RESERVE IN DEFENSIVE OPERATIONS
  6-62. The defense plan retains a reserve regardless of the defensive operation assigned. The reserve is that
  portion of a body of troops that is withheld from action at the beginning of an engagement to be available for
  a decisive movement (ADP 3-90). The reserve is more difficult to resource in the mobile defense because so
  much of the available combat power is allocated to the striking force.
  6-63. EFSTs for the reserve are as follows:
  * Plan fires to support the commitment of the reserve during movement.
  * Plan fires to strike at objectives in depth as enemy dispositions are revealed. This is to support the
  committed reserves and to break up the enemy's coordination of the attack in the area defense.
  * Plan fires on the enemy's flanks and rear where counterattacking forces are committed in the
  mobile defense.
  * Plan fires to deceive the enemy into thinking the reserve is committed elsewhere.
  * Plan for FSCMs such as an RFL in case of converging forces in the mobile defense or a RFA to
  safeguard strongpoints in the area defense.
  * Plan to rearm, refit, and refuel organic and supporting FS before assuming on-order missions.
  6-64. As in the offense, a support relationship of GS or GSR is best for artillery units designated to support
  reserves once committed. Once the reserve is committed, organic FA is augmented by other lethal and
  nonlethal attack/delivery platforms. Unnecessary changes in organization and time-consuming movements
  should be avoided to ensure adequate support for the committed reserve.