Look at the first page of BIOS, what version of BIOS you have now?
As shown in my screenshots, old BIOS was E4D6_HI-122LP.221 from 22. 3. 2016 (I have tablet only 2 days) and new after flash is E4D6_HI-122LP.223 from 28. 4. 2016.
The name of the new BIOS archive is Lateset Dualboot Hi12 BIOS(remain KEY, solve wifi disconnet issue).rar