Cool the reefer trailer down before it backs into the dock.
June is when the produce out of the Southeast starts to move in volume. A trailer that is still hot when the doors open puts that heat into the product. You will hear about it as a claim, not as a weather report.
Set the temperature before the load
The set point belongs on the rate confirmation and on the bill of lading. Run the unit until the trailer is at that temperature, then load. Do not load a warm box and hope the unit catches up on the road.
If the shipper and the receiver do not agree on the set point, do not guess. One number, written down, before the forklift starts.