Last month I was given dates of 4/24-7/4/2006 for the refurb. This was from someone who works in WDW Shops. It should be open when the next POTC movie is released
That would make sense because it will wrap right in with the Movie opening. Since it is not as big a re-do as DisneyLand's starting end of April instead of Mid March would sound about right and it would make no sense to have it closed for all of May, June, and July and miss the movie by 2 months so I don't think May to Sept. sounds accurate.