Go to the Setup > Vendors tab and click on the vendor you want to configure.

The vendor information window will open, click on the Shipping Schedule tab and select the Ship from Vendor Days in order to get the Vendor Ship Day. If the setting Inbound Truck Freight is enabled, you will be able to associate a carrier for each vendor Ship Day which will be suggested once users enter a ship date during a PO creation. As a final comment, these settings are also reflected on the Bulk Purchasing Mode where the system will load the ship date for each vendor. If the vendor has a specific shipping schedule it will have priority over the Port Management Settings, if the vendor does not have a shipping schedule the system will use the Port Management Settings in order to load the ship date.