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No chinese variant device never possible to upgrade directly to G.

still corrup to update 5.11.1a to 5.12g i was download twice

Already said bro you not able to update A version to G directly

can u teach me how to flash a to g?plizzz

1- install 4.2.8.x A on your device
2- root device
3- install super su from the play store
4- download cloud.mail.ru/public/EYpv/u5j5YXek9
5- create folder named int_mx4_pro on the root of your device
6- paste the extracted files on that folder
7- download terminal emulator from play store
8- open terminal emulator
9- write su and press grand on the pop up dialog
10- write cd /sdcard/int_mx4_pro and after that write sh install
11- the phone will reboot itself
12- download 5.1.12.0G and open it from file manager
13- check erase data and install

thanks bro....

Work for me as well,
Thank for nice post