John ji i bought 21400PE yesterday as i had written on this thread too. I sold half of my holding in the morning and the SL for the rest was either price of the underlying going above 21720 (yesterday's high) or the OBV going above yesterday's PDC levels. I know for a fact that options (and that also weekly) lose value very fast. In this case had i kept an SL based on the price of the option, (like you have explained) the SL would have triggered twice and i would have had to buy them again at a higher price. The reason i chose 21400 strike price was that i thought that even if BN were to go up to 21720 today, the option would have still been worth 30 (almost half of my purchase) I went into this trade with full consideration and knowledge of my risk. I hope i have answered your question.