Yes, the "10am-11pm" was a typo, and it's been corrected.
However, since the first one (the Eastern time) is the one out of synch with your Aussie clock, I don't have a real answer for you, other than "it's wrong".
If the maintenance will start at 1 PM Eastern Daylight Time today (Oct. 16th) in the US, then that will be 8 PM Eastern Summer Time in Australia on Oct. 15th. (Summer Time started a few weeks ago and is GMT +11 in QLD.)
Time math is one of the more difficult concepts, in my opinion.