There is no way the production cars will be operating by the time the second ave extension opens (if it opens at the end of the year). The prototype consist will need to complete qual testing and burn in, which usually takes up to a year or more, before production cars can even enter service. From what I know, the 179's haven't been delivered yet. Therefore, the earliest I can see production cars running, unless MTA tries to accelerate the testing period for the prototype cars, is sometime next summer or fall.