http://news.xinhuanet.com/english/2004-06/16/content_1527688.htm
WASHINGTON, June 15 (Xinhuanet) — The independent commission probing the Sept. 11, 2001, attacks has found evidence suggesting al-Qaida leaders had intended to launch the attacks in May or Juneof that year, but postponed the plan because lead hijacker MohamedAtta was not ready, officials familiar with the panel’s findings said on Tuesday.
New evidence gathered by the commission indicates that Khalid Sheik Mohammed, mastermind of the attacks, persuaded al-Qaida leader Osama bin Laden to postpone the attacks by several months because of the organizational problems, The Washington Post reported Tuesday.
Until now, federal investigators have said the evidence indicates that the attacks were likely planned for a narrow time frame around Sept. 11. If there had been an alternate date, investigators have said, it was probably later in the year.