I might drag the suitcase out of the closet the day before, but having everything packed more than an hour or two before departure time would be advanced preparation for me.
And is there something wrong with packing that early? (snicker) Actually, my wife starts packing at least a week before a major trip. Then she shrieks at me "when are you going to start packing?!!!? " I yawn and reply that the morning of departure is usually enough time. As if you forget to pack toothpaste or shampoo, you won't be able to buy any along the way.