When an Amazon shipment is placed, your confirmed carrier will book an Amazon appointment for the specific delivery warehouse code you entered in the order. That is the reason why, when booking the order, you have to enter the day from which the pallets can be picked up. With that information the carrier can request a delivery timeslot at Amazon.
The delivery appointment the carrier receives from Amazon depends on how busy that Amazon warehouse is. It is difficult to give an estimation of the time needed for an Amazon shipment, but our carriers try their best to deliver your goods as soon as possible.
Please be aware some of our carriers will only pick up the shipment when the delivery date is known, so take into account that the pallets might have to be stored for a while after booking the shipment.