BBB, update to latest Angstrom Kernel

I am a relatively new user of the BBB. How do I know the current version of the Angstrom kernel on my device? How do I update and upgrade it?

I have tried “opkg update && opkg upgrade” but all of the downloads failed. I believe this is because the angstrom servers are down according to

I have found, what appears to be, the 3.8 angstrom kernel here but I have no idea how to put it on to my BBB.

Any help would be great.