The Bombay Stock Exchange benchmark Sensex gained over 70 points in opening trade on Monday on the first trading session in the New Year. Sensex was up by 42. 84 points, trading at 17507.65 while Nifty was trading, 13.45 points up at 5214.50 when news last came in. Dalal Street started the day an hour early at 9 am, as the exchanges decided go ahead with the new timing, despite protests from some quarters. With a view to better aligning the domestic markets with the other Asian bourses, both Bombay Stock Exchange and the National Stock Exchange had, late last month, announced an advance in their trading timing to 9am from 9.55am earlier. The market will continue to close at 3.30pm.