Singapore Gateway Latency Issues (as of today)

It's possible your ISP has changed the route they use to get to the Singapore servers. You could try download WinMTR and run it against sng.login.pathofexile.com to see what the route is doing. Post the output here if you want a hand interpreting it.

Your WinMTR output is just plain bizarre, I don't know what could mangle it like that.

Your tracert though suggests the problem is between your ISP and equinix. I would assume they used to route through someone else. You could try contact your ISP and ask if they can do anything about it... possibly a long shot, but doesn't hurt to ask.