code: function defineInitiateBatchTask() {
      const taskDef = TaskDef.defineTask(initiateBatch.name, initiateBatch, batchAndCancellableSettings);
      taskDef.defineSubTask(extractAndSequenceMessages.name, extractAndSequenceMessages, batchSettings);
      taskDef.defineSubTask(loadBatchState.name, loadBatchState, batchSettings);
      taskDef.defineSubTask(reviveTasks.name, reviveTasks, batchSettings);
      taskDef.defineSubTask(preProcessBatch.name, preProcessBatch, batchSettings);
      return taskDef;
    }
docs: Defines the initiate batch task (and its sub-tasks) to be used to track the state of the initiating phase.
  @returns {InitiateBatchTaskDef} a new initiate batch task definition (with its sub-task definitions)