Schedule Life Cycles can be separated into two basic categories. One is the life cycle of the program schedule, and the second is the life cycle of the Product Breakdown Structure and Fragnets developed during the program to be used for future programs.

The schedule usually starts its life during the proposal stage of the program.  It is sufficiently developed in order to assure the contractor and customer that the program has a plan to successfully complete the program on time and on budget.  The schedule that is created needs to include tasks from the authorization to proceed to the completion of the system.  This becomes the framework for the program schedule.  As the program matures, to the execution phase, which includes design and production of the system, detail is added in the form of control accounts to satisfy the need for a detailed schedule using rolling wave techniques.

As control accounts are completed, the detail in those control accounts can be saved for use on future programs.

The technique of building schedules based on clearly defined Summary Level Planning Package tasks offers the user the opportunity to define the control accounts and their underlying work packages into Fragnets which can be warehoused and used on future programs.  If the Summary Level Planning Package tasks can be clearly defined with starting and finishing criteria, then the underlying control accounts can also be clearly defined, affording the contractor the opportunity to match them to future structured schedule frameworks on future programs.