Did Joseph or you change the original DNS entry for www.tex.ac.uk? It now points directly to Github, so my redirect cannot work.
nslookup www.tex.ac.uk
Server: 213.133.100.100
Address: 213.133.100.100#53
Non-authoritative answer:
www.tex.ac.uk canonical name = texfaq.org.
Name: texfaq.org
Address: 185.199.109.153