code: def migrateDown(self):
          
          subStore = self.store.parent.getItemByID(self.store.idInParent)
          ssph = self.store.parent.findUnique(
              _SubSchedulerParentHook,
              _SubSchedulerParentHook.subStore == subStore,
              default=None)
          if ssph is not None:
              te = self.store.parent.findUnique(TimedEvent,
                                                TimedEvent.runnable == ssph,
                                                default=None)
              if te is not None:
                  te.deleteFromStore()
              ssph.deleteFromStore()
docs: Remove the components in the site store for this SubScheduler.