If BANKNIFTY below 39850 than short 40000 CE 23 mar expiry if bank nifty above 40086 short 40000 PE 23 Mar Expiry ( for seller)
or
If BANKNIFTY below 39850 than buy 40000 PE 23 mar expiry if bank nifty above 40086 buy 40000 CE 23 Mar expiry ( for buyer )
Trade after 9.30