BBC5 Strategy is based on Bollinger Band indicator. I have used two Bollinger band with different time period of 26 and 20 with difference of 1 period in them. For a buy trade candle has to close outside of Bollinger Band and lower level of Bollinger Bands should be rising compared to previous values. Vice versa for sell trade 15 min candle has to close outside of Bollinger Band and Upper level of Bollinger band should be falling over previous value.