So when is the actual patch?

Big Bang is happening on December 7.

http://maplestory.nexon.net/News/News.as...ageIndex=1

Right below "Click here to see the entire lyric" link.

I'd guess they're patching late tonight/early tomorrow so the game is up and running by tomorrow afternoon. It fits with the time line event on the rings (They will probably at least try to make it so the game is up in time for people to do the full event, though emergencies may prevent that) and makes the most sense to me as far as keeping in line with their "December 7" post.