Mobile browsers ignoring Access-Control-Max-Age

I am doing multiple cross domain uploads using CORS, on a very super slow connection (low signal HSPA or 3G), I find that the client re-requests OPTIONS for almost every POST (1-2 minutes interval). I have already set the preflight resolution to 10 minutes (add_header Access-Control-Max-Age 600;) and I confirmed to the inspector that the mobile client is receiving this header. Is there any other header that needs to be added to prevent the client from making OPTIONS requests repeatedly?

I have read other threads, but none of them provided any solution to my problem:

Is Chrome ignoring Control-Cache: max-age?

CORS Access-Control-Max-Age Ignored

Everyone says the browser should accept a 10 minute cache cache if I tweak this header, but that's not what I'm experiencing at all. And these repeated requests for OPTIONS only degrade the experience of my slow users, slowing down the download speed even more.

I have cross-tagged this issue for google chrome issue tracker here: https://code.google.com/p/chromium/issues/detail?id=131368#c10 with some screenshots from the inspector.