How to downgrade bios Gigabyte Z170-Gaming K3

[kyniu92]

Hi. I'm looking for information, how to downgrade bios. I want to do nonk oc, but my motherboard have f2 bios from 10-03-2016. I would like to install bios f2c from december 2015. Can someone tell how to do this? I found this bios, but if i doing q-flash bios is still f2 :/
Sorry for my english