B6 went from 162 --> 156 --> 150 seats in an attempt to reduce weight (increase range) and ultimately to go from 4 required FA to 3 @ 1/50 seats.
B6 though lacking ovens and other legacy galley equipment was always "heavy" as a result of IFE hardware and above average loads.
Their move to go back to 162 seats will only increase tech stops on their legacy 320's WB in the winter.