The first thing you should know is that the Cast Members on the phone and via email at DLR often have no clue what is happening (especially not outside of a certain time window), and they can either give outdated info or incorrect info -- or no info at all. It happens time and time again. So the CM who told mom4scrapbooking that IASW would close down on 11/1 is almost certainly incorrect.
What usually happens is that IASW closes down maybe one or two weeks before October ends (or on one of the last 2 weekends in October), to receive its holiday overlay. It's a Small World Holiday will most likely open on 11/7, if history and tradition repeat this year, so they (Disney) need time (at least 2-1/2 weeks) to get it into full holiday mode -- and closing it on 11/1 just would not give them enough time.
The holidays don't officially begin at DLR until 11/13, but IASWH usually starts before the holidays officially start, which is why 11/7 is likely.