If we call the inital stocking first generation, then my guess would be lots of third generation fish and possibly some fourth generation by the die-out time. However, they stop reproducing below 68 degrees and that happens considerably in advance of the die-off in East Texas.
In my first season with Tilapia several years ago, I stocked some in a pond without predators, just for fun. At the die-off, there were hundreds of 3,4 and 5 inch fish...zero small ones and zero large ones. The die-off happened Christmas time, but reproduction must have shut down much earlier as indicated by the complete absence of fry.
