def get_load_plan(self):
        """
        return load plan (timestamps generator)
        """
        if self.rps_schedule and self.instances_schedule:
            raise StepperConfigurationError(
                'Both rps and instances schedules specified. You must specify only one of them'
            )
        elif self.rps_schedule:
            info.status.publish('loadscheme', self.rps_schedule)
            return lp.create(self.rps_schedule)
        elif self.instances_schedule:
            info.status.publish('loadscheme', self.instances_schedule)
            return ip.create(self.instances_schedule)
        else:
            self.instances_schedule = []
            info.status.publish('loadscheme', self.instances_schedule)
            return ip.create(self.instances_schedule)