Today will be gap up opening in BANKNIFTY . After opening if banknifty sustain above 42550 level then possible upside rally of 400-500 points upto 42950 Level.If banknifty start trading below 42450 level then possible Downside rally of 400-500 points upto 42050 Level. And this rally can extend for another 400 points if it gives breakout of 41950 level.