They can dual Aerobridge board to keep turns quicker L1 & L2.
The L2 door is an emergency only exit on the current 321 and is optioned to be deactivated on the NEO.
Press release*| Airbus, a leading aircraft manufacturer
The first new option consists of an additional over-wing exit door which raises the current maximum exit limit so operators can make even more use of the available cabin floor space. When this new option is combined with the Space-Flex aft cabin configuration, the A321neo can accommodate up to 236 seats, 16 seats more than today’s maximum seating, which leads to a reduction in seat mile costs of five percent.
In conjunction with the additional over-wing exit door, a second new option is available whereby the forward exit is de-activated. This creates a seamless, undivided forward cabin allowing additional seats and even more flexibility in multi-class seat arrangements. This option will be of particular use in longer range markets where high comfort standards are needed in Premium class.