Some Apple retail employees have reportedly been told to discourage customers from trying to buy an iPhone Duo without a pre-order on its October 23 launch day. Staff expect little or no stock for walk-in purchases, though it is unclear how widely the guidance applies.

Apple’s online store asks customers to check again on October 24 for pickup availability. That message does not promise that stores will have devices then. Pickup reservations appeared briefly when pre-orders opened before the option was turned off.

Online delivery estimates slipped quickly after pre-orders began. Within 30 minutes, every iPhone Duo configuration in Apple’s U.S. store showed a January 25 shipping estimate. Apple has described demand as unusually strong, while the extent of any launch-day store shortage remains uncertain.