For index futures, RTH session runs upto 1615 EST. Why does IB enforce overnight maintenance margin at 1600 EST? Many a times, I want to continue holding positions till 1615, but IB's policy makes it impossible to hold the position to eod. Do other brokers like Advantage etc. also start overnight maintenance margin at 1600 EST? Do other traders also feel this hampers their trading? Is there a way we can collectively lobby with IB to extend their change in overnight margin time to 1615 EST?