For shoonya preparation, 20 min sukh kriya followed by 20 min Om chanting is recommended per session.

How about following it with fluttering of breath & rest of Shambhavi steps to culminate it as Shambhavi ? Any cons that we should NOT do such a thing ? Shambhavi guidelines mandate minimum of 5-6 min for sukh kriya & 21 om chantings. But I guess more can be done.

Am I missing something ?