This summary is from memory; feel free to correct anything unclear or quite correct. 

I believe the target was for POET to own 47% of the JV once Sanan completed all of the investments that were expected to be necessary. Of this 47%, Suresh has mentioned interest from tech investors in China who could buy some of that. Eventually, the JV would IPO on the Chinese stock market, which had bullish valuations for tech companies compared to the West's stock markets. POET could sell off shares for further liquidity. 

This makes sense to me, because the need for capital is greater than the need for steady revenue from China, which will always be discounted due to concerns about China. It will never move the needle for POET's stock price as much as Western and other Asian revenue will.

POET will continually sell wafers made under contract by Silterra or others with POET technology inside.  The JV depends on the IP manufactured into those wafers, as it was founded to leverage this technology only for the 100G to 400G markets. The JV slices the wafers into chips and does the rest of the preparation to sell to module makers.

They could expand to higher speeds if this works out well for POET. 

I have always viewed this JV with Sanan as a huge indicator of POET's technology leadership. Sanan is more than capable of vetting this tech. The terms are also quite good for such a marriage.