CAUTION : I'm not responsible for any damage to your device.Use at your own risk
I want to introduce to you a Team Win Recovery Project 184.108.40.206 for Onda V972.
I think it will be usefull and for Onda V812, and V971, maybe other A31 tablets.
That TWRP works on 32 Gb version of Onda V972.
Installation TWRP Recovery on Onda V972
Before installing TWRP, you need to get root. All latest stock firmware comes with root, you need only install Superuser or SuperSU from Play Market
Download the Onda_V972_TWRP.zip from that post and extract it to any folder on your computer.
Copy all three files from your computer internal disk (ONDA_MID on you computer and /sdcard on tablet)
Install the application Terminal on the tablet and run it.
From the terminal emulator enter the following command:
busybox sh /sdcard/install-recovery.sh
busybox sh /sdcard/reboot-recovery.sh
You can also use the standard way of loading in recovery - While the tablet is off press Home button and holding it press the Power button untill 4 core logo appears.
If something goes wrong, you need to flash the firmware via Stock PhoenixSuit and during flashing select "YES" to the question about formatting.
It is not bug free version, there is a error: Unable to mount '/recovery' I will try to fix all bugs.
I repeat: Use it on your own risk!
Thanks to Dees_Troy and all TWRP team for great work!
Thanks to darkrickpr from slatedroid for base TWRP
Thanks to hariprasadiit for his CWM port and his post.