The free hosting nameservers are geo-distributed, meaning there are different servers across the globe and whenever you do a DNS lookup, your request gets routed to the nearest server.
There have been issues in the past where one location went down, resulting in websites being unreachable from some parts of the world.
However, as far as I know, there is only one location in Europe, which doesn’t really explain why only UK users are affected. If the EU nodes are down, then I should be affected too. And it doesn’t really explain the issues from India either.