Thats actually a good question to me... But besides those lines they could likely put some cars to serve the portion of the Second Ave Subway, primarily the and future if the next phases are built. The could maybe get them too but thats "only my prediction." As far as any other lines, to early to predict.
If all goes well and steady with the R211 order which in total is 1,025 with a futher option order of 520 more totaling to 1,545, I think it all depends on were the R179s will ultimately end up and what lines end up with some service enhancements.