Just to add to this, I'm also having issues with my 10Gb Mellanox card (MCX311A). I'm running on a ryzen 3700x and asrock X470D4U. Everything was working before the update and even completely resetting my network config and rules did not help. Unraid refused to recognize the mellanox card as eth0.
EDIT: I was able to solve this by connecting a monitor to my server and booting into GUI mode, then enabling bonding on eth0 and adding the mellanox nic as a bonding member (eth0 and eth3 in my case).