We usually go in October (for the last 6 years) and this is the first year we've gone then that I can remember it being closed. We asked a CM about it and they said they were doing a major refurb, including draining all the water out to do something (clean? replace?) the underwater tracks that get rusted/worn over time, so this is something they schedule every 3 years or so (it seemed like a very rough estimate though).