When confirming an order with the customer, it is good to confirm a time window as well. Between 2-4, between noon and 4, etc.
Different business lines may require tighter windows than others. Perhaps a customer is willing to accept Rock at any time during the day, but Asphalt would need to be expected in advance. Or, perhaps when speaking about replenishment, receiving a material at a specific time is crucial to not running out of material and stopping production.