https://downforeveryoneorjustme.com/elpa.gnu.org
Found a post on reddit from an emacs maintainer suggesting that we should email this list when ELPA is down. I tried to access https://lists.gnu.org/mailman/listinfo/savannah-hackers-public to find the web archive to see if its already been reported but that appears to also be down, so my apologies if this has already been reported.