Hello Steve,
Thank you for the information very helpful, it is quite doubful that these Postal Services will switch from their current shipment system to a new one supposed to collect tariffs at the starting point for two main reasons (in my modest opinion of course!)
1- time, money and efforts involved to make such a change.
2- Direction of wind is changing so fast and unpredictably these days in the USA, that taking to the sea without knowing what the sea state will be tomorrow is a complete nonsense.
Best regards from Normandie,
Jacques