The trace right at the SMA connector is cut, so I'm guessing there is a jumper to only one side and the other is not connected.
The ground plane is part of the antenna so how the chip is placed in relation to it is important. What I'm guessing is they did the 2nd trace to give the user the ability to evaluate performance in the other orientation compared to the long edge of the board. (Educated guess only, listen to others if they know better.)