Enabling locked undervolt after BIOS upgrade.

Machine: Acer Predator Helios 300 [G3-571]
CPU: Intel(R) Core™ i7-7700HQ [Kabylake]
BIOS: Insyde Corp. V1.22, 15-Mar-19

Problem description: Recently I had the misfortune of upgrading my bios using the latest executable from the OEM website. I refer to it as a misfortune because it disabled the ability to tune the voltage of my CPU, which I could do easily with the help of Intel XTU. Downgrade by "official" means is not supported, so I am exploring unofficial ways of getting back the lost functionality of undervolting. Being a total noob in BIOS modding I wanted to ask experienced people here about what would be the least risky approach to achieve that? Is force downgrading BIOS the best approach? Or is modifying the current BIOS image a better option? Additionally, if BIOS gets bricked, how hard is it typically to unbrick it?