Was it AMD or motherboard manufacturers blocking CPU support? I thought it was companies like Asus which didn't want to add additional CPU support for their EOL b350 products.AMD has stopped blocking CPU support, albeit recently. I think that may be why this BIOS was just posted. See this article. https://www.anandtech.com/show/17313/ryzen-7-5800x3d-launches-april-20th-plus-6-new-low-mid-range-ryzen-chips
They will be supporting Vermeer and others including the new 5800X3D on 300 series boards, I think this BIOS was released early by gigabyte now that this was announced. I would expect this support for many boards soon.