Even if EY can't keep them for more than another year, the salaries would allow them to keep working on their pet project for that long and push out a few "good enough" features just to keep the community happy. After that they can jump ship again and start their own JRuby consulting firm; all it takes is just one or two big clients that need support. The fact that they're currently employed to maintain JRuby would certainly guarantee big firms taking notice and consider using it ("hey, there is actually someone we can pay for support", etc.)