Found this tutorial and it worked:)
I’ll give a basic guide a shot:
You will need: X98 plus dualboot tablet, micro usb to usb cable (the one that comes with the tablet), a windows pc with a usb port
Make sure your tablet is fully charged before starting
download Mirek’s zip file on your windows pc and extract to the C: folder (use 7zip, as you can see above not all extraction programs are equal)
install the two application files (FIRST_INSTALL_IT and SECOND_INSTALL_IT) by double clicking on them and following the instructions
with the tablet fully powered off hold down the power button and both volume up and volume down to boot into DnX mode
the screen should turn on and display the Teclast logo with DnX fastboot above in yellow
plug the tablet into your pc using the usb cable
on your pc in the extracted folder double click on the FLASHER_v1.0 batch file and follow the instructions (press 1 to keep android apps and data, 2 for clean install, e to exit)
when it finishes unplug and reboot your tablet, the first boot will take some time sitting at a screen saying android
Hope that helps