I know that most people recommend checking in the morning but usually stores get their deliveries either mid morning or afternoon in my experience.Drat, nothing for pickup near me yet. My guess is South Florida is a high demand area.
When people talk about 6am it's worth noting that most employees don't get to the stores til 7am or after and there would still be work to be done to get everything into inventory. The mid day stuff will just happen as the employees work through everything.