Data Management Capabilities > Managing Plans > Plan Schedule > Subplan
  
Subplan
A subplan is an activity in a plan that acts as reference or proxy for another plan or plan activity. You can use a subplan to break down a large plan into separate pieces to be managed and executed by separate teams. The referenced plan is referred to as a child plan and referencing plan is referred to as a parent plan. There can be multiple parents for a child plan.
The only relationship between a plan with other context plans is through a subplan. For more information, see Subplan Constraints.
You can use subplans to link plans in the same contexts or in other contexts. If a subplan links to a plan in other contexts, then there is no sharing or inheritance of action items, meetings, resources, or access rights between a parent and any related subplans.
When plan is in a scheduled state, all the schedule information is rolled up to the subplan. When a plan starts executing, all the tracking information is rolled up to the subplan.
There are number of limitations in how Windchill handles subplan relationships. It is essential to understand the relationship of plan information in a subplan to parent projects or programs to determine how you can take best advantage of the benefits of a subplan.
A propagate change in the start date in the parent plan, cannot influence the start date of the subplan. Propagation only occurs from the subplan to the parent plan. For example, if the reference plan or the estimated finish date for an activity is pushed out, then information is propagated
In the case of automatic execution, a child plan cannot start unless all parent plans are started.
You cannot define predecessor relationships for a subplan. But you can establish predecessor relationships between subplans and other activities in a parent plan. As a result, you can use subplans to drive activities in a parent plan but cannot use activities in a parent plan to drive subplans.