Fluff: The predecessor of the famous A-Wing, the A-Wing Prototype already featured many design details of the later production series model.
During the further development some effort was put into improving the flight dynamics and engine shielding by Rebel engineers which lead to the more curvier and compact shape of the later production model.
The original heavy laser weapons of the prototype were replaced with slightly lighter laser versions to reduce power strain on the A-Wing´s reactor.
Gamewise it will serve as an A-Wing and hopefully see some action soon! :D