About Push Planning
This topic applies only to APS.
If the system cannot find enough on-hand inventory, planned supplies, 
 or resource capacity to pull 
 plan a demand within the time between the due date and the current 
 date, it instead push plans the demand forward from the current 
 date. The system push plans a demand according to this sequence:
	- Calculate the end-item quantity needed. Allocate on-hand inventory 
	 to satisfy the end-item demand quantity. 
	NOTE: When APS 
	 allocates inventory to a demand, it considers the combined total of 
	 all inventory at all warehouses (at a given site) in which the Dedicated 
	 Inventory option is NOT selected. 
- Pass any remaining end-item demand quantity to the component materials, 
	 down to the lowest levels in the bill of material. Allocate on-hand 
	 inventory to satisfy the demand quantity of the components.
- Plan the component materials in the lowest levels of the bill of 
	 material. This step consists of planning steps in the routing for 
	 manufactured components or moving out to the lead time for purchased 
	 components. For manufactured components, each operation in the component's 
	 routing is planned in forward sequence (starting with the first operation). 
	 The system checks several resource combinations to find the combination 
	 that can finish the work the fastest (the number of combinations to 
	 check is specified in the Push 
	 Iterations planning parameter). The result is the component material's 
	 earliest-possible completion date, which sets the start date of its 
	 parent end-item's first operation.
- Search for available planned supplies, starting with the current 
	 date and searching out to the date calculated in the previous step. 
	 Allocate supplies only if the entire demand quantity can be satisfied.
- When forward planning is finished, the end-item completion date 
	 becomes the demand's Projected date.
- The system may plan non-critical operations earlier than they are 
	 actually needed to meet the demand. To optimize the plan, the system 
	 runs a series of additional pull-planning iterations starting from 
	 the demand's new projected date. 
	
		- Pull plan starting from the projected completion date. If this 
		 plan fails (that is, if it projects a start date in the past), 
		 the system then pull plans the demand from the end of the Plan 
		 Horizon.
- Incrementally pull plan between the projected completion date 
		 from the above push plan (or between the need date and the Plan 
		 Horizon, if the above push failed) and the demand's need date 
		 to find a feasible plan that is within Pull Tolerance (see Planning 
		 Pull Tolerance or ATP/CTP 
		 Pull Tolerance) days of the optimal projected date. For example, 
		 the first iteration pulls from the midpoint between the projected 
		 date and the need date. If that pull plan succeeds, the next iteration 
		 pulls from the midpoint between that new projected date and the 
		 need date. The process incrementally moves closer to the need 
		 date until it finds a plan that a) doesn't calculate a start date 
		 in the past AND b) has a projected completion date that is within 
		 the Pull Tolerance days of being the optimal date.
 
NOTE: If the system 
 is unable to push plan a demand in the time between the current date and 
 the end of the Plan Horizon, the demand is displayed as "blocked" 
 on the planning output forms and reports and cannot be planned. See About 
 Blocked Demands for more information.
Related Topics
APS Overview
About 
 the Planning Process