Every FCL full container export shipment follows four fixed port/carrier deadlines: CY Open, SI Cut, CV Cut (Heavy Container Closing), and CY Customs Release Closing. Most new exporters and junior freight agents confuse these four critical timelines, leading to rollover cargo, heavy late come surcharges, customs inspection risks and delayed customer deliveries. This complete logistics guide clearly defines each cut-off term, sorts their standard time sequence, explains US route exclusive AMS filing rules, lists all penalties for missing deadlines, and shares actionable tips to avoid extra logistics costs.