Some years ago, when connectivity within the pacific region was less reliable, we added a small proxy server in Singapore which forwarded sessions down a VPN connection to our datacentre in New York.
The world has moved on, and this service is barely used. Reading the logs it's almost all search engines scanning our help pages, which is just going to direct people to the slow proxy copies rather than the originals.
So as of today, the sg.* hostnames point directly to our main New York addresses, and the Singapore proxy will be shut down.