most likely it's the same problem as with the launcher, where they are somehow losing dns entries for their domains. Seeing as dns updates generally can take up to 24 hours to update depending on the location, it's something that's impossible to do quickly.
That said, if it's not dns, it's probably the fact that it's sunday. While a datacenter generally has 24/7 support, nc is probably hosted on a virtual server, which means a lot of the support has to be done by the owners.