Okay, then. Atta's movements in June are not as documented as those in July and August were. The only documented Atta sightings were on:
* an unspecified date in June: Atta joined a Jim Woolards World Gym in Delray Beach, FL. I've never seen the date reported.
* June 12/13, when he and other hijackers moved into the Tara Garden condo at 10001 W. Atlantic Blvd. in Coral Springs FL.
* June 28, when he flew to Las Vegas to meet with the other three pilots. After this point, Atta's movements until his return from Spain on July 19th are fairly trackable.
So, if only five days would be required, there were numerous opportunities in early June.