def METHOD_NAME(self):
    offset, target_day, enrollment = self.prepare_course_data()
    with patch.object(tasks, 'ace') as mock_ace:
        self.task().apply(kwargs=dict(
            site_id=self.site_config.site.id,
            target_day_str=serialize(target_day),
            day_offset=offset,
            bin_num=self._calculate_bin_for_user(enrollment.user),
        ))
        assert mock_ace.send.called