When setting up a trade route, players can select a multitude of options on how to pickup cargo, but only have two for dropping off cargo. Store In Warehouse & Sell To Market, which are setup via the singular option of Store In Port X (Yes/No).
Store in Port options should be updated to be called "Port Storage Policy" with the below options:
-Sell to Market
Basic option that sells to market. No cargo is sent to warehouse
-Store in Warehouse Until Full, then Sell to Market
Stores in warehouse until the warehouse is full. All remaining cargo is sold to the market.
-Store in Warehouse Until (X), then Sell to Market
Stores in warehouse until Cargo Stored in Warehouse reaches X or warehouse is full (which ever is the lesser amount). All remaining cargo is sold to market. Allows a player to define a specific amount of cargo they want to store before selling to the market.
Additional options could be added for other trade features such trading to other players warehouses, etc.
I'll update as needed.
+1