Reminds me of a moment I had once. Wife and I were going bareboat cruising for a week in the Caribbean. Then I coincidentally needed to be in Puerto Rico for the follow week to work. I didn't want to drag formal work and evening wear around on the bareboat, so we decided to ship our work luggage directly to the hotel in PR, so it would be waiting for us.The traffic carried by ships cannot be diverted to rail, or vice versa.
I take our bags to the local shipping store and they look up all the rates. US Post Office would technically work between mainland and PR, but he advises me that arrival time is not guaranteed, nor even estimated. While I have two more weeks, before I'll get to the hotel, he said it was still a gamble. And that was long ago, today I wouldn't trust them to get a letter across town.
He looks up FedEx, etc, and quotes $700 for two oversized pieces of luggage. Then says, unfortunately, they don't have ground service to PR.