I'd call that pretty recent :) – fwupdmgr wasn't supported (not as in 'you're on your own', but 'blobs not published to registry') until a few years ago. EFI shell update wasn't available early on. When I say I'm trying to, I'm actually struggling to establish if it's even possible without at least using Windows to jump to a certain version after which I can use EFI/fwupdmgr.