Heres the main website to download firmware for the Nextway f9x a31 tablet with a 9.7inch screen.
nextway | ?? - ???? - ?? + ????
Here is the direct link to the 1.35 firmware
Once again I reccomend using pheonix suite to flash this, as that is the easiest way with least chances of errors.
P.s after flashing the update, the language will be in Chinese, and you have to find your way into the settings and change it there.