Blueprints must first be configured in Setup > Schedule in order to use them on the Planning board. The authority permission, Scheduling: Planning must be granted to use this feature.
Use shift split when creating an event that spans more than one shift for one or more days AND you want the application to automatically create blueprint instances on the planning board using the appropriate shift from the selected Shift Split group and within the date range supplied. For more information review About Blueprint Shift Splits. To deploy a blueprint using multiple shifts on the Planning Board: