Store managers for Apple and AT&T retail stores are preparing for an unusually large level of traffic on June 29, at 6PM. In preparation for a proper introduction of the iPhone, all participating stores will close down at 4:30PM local time, kick all customers out and then reopen 90-minutes later.

Do not expect to arrive at the store and simply stroll in to purchase the iPhone. Most likely there will be lines of campers outside anxiously waiting to get their dirty hands on the iPhone. So how will Apple and AT&T handle crowd control? Store managers on both sides have been told to forewarn their landlords and acquire stanchions. The AT&T communication applies to all AT&T retail stores except those physically located inside shopping malls. Temp staff may also be brought on to assist in the madness.

"In order to prepare for the launch we plan to close our stores 1 1/2 hours prior to launch time, at 4:30 PM," the memo said. "If the landlord questions your plan to close the store from 4:30 - 6:00 PM, explain that all AT&T and Apple stores nationwide intend to follow this plan."

"You and your landlord need to determine an area outside the store where customer lines should form and whether or not stanchions (standards & ropes or chains) for crowd control are needed," AT&T's corporate offices wrote in memo to store managers.

AT&T stores will remain open until 10:00PM on the eve of June 29, according to the memo. As of right now, it’s not clear if Apple stores will follow the same schedule.

AT&T iPhone launch deets: crowd control [Via here and here]