Some of the wares might have been unloaded, and with the remaining wares, no other port can be built. The ship would therefore have to return to the starting/nearest port (similar to "Cancel expedition"). There it could either
- be refilled so that the player can start another expedition
- be emptied.
I prefer option 1, because the player might want to build a port somewhere else. If he does not want that, cancelling the expedition is probably faster than emptying the ship first and then starting a new expedition.
Some of the wares might have been unloaded, and with the remaining wares, no other port can be built. The ship would therefore have to return to the starting/nearest port (similar to "Cancel expedition"). There it could either
- be refilled so that the player can start another expedition
- be emptied.
I prefer option 1, because the player might want to build a port somewhere else. If he does not want that, cancelling the expedition is probably faster than emptying the ship first and then starting a new expedition.