If u can read chinese, would recommend this article.
One of the concern for CAC is that it would be really hard to promote FC31 if they have never exported any 4th gen fighter. I would believe an exPLAAF J10 with export license of AL31 FN would be the so called FC20. Since the early J10 would need MLU anyway, for CAC, it will be more economic to keep producing J10 b/ c other than try to reopen J10a's production line.
J31 is a SAC product, not CAC. That fact alone would sink the theory from that article, since even if J10s are exported, it would be CAC who sold them, and SAC (the makers of the J31) would still have no experience exporting 4th gen fighters.
There is also the fact that JF17s have already been exported to at least two customers, so CAC has already broken it's 4th gen duck.
The J10A being finally approached for export would be entirely down to the PLAAF, who probably insisted that the best fighters available cannot be exported until they themselves have something better.
Thus, as they are getting their first operational J10B/Cs, they are now finally winning to allow CAC to export the J10A.
It might not be as cost efficient or attractive to potential buyers as selling Bs and Cs, but in China just categorically doesn't mess around with national security.