If you do the local bus for a tour of the island beware of very long lines and if you get off the bus at a stop you may not be able to get back the next one. Also beware that they take British pounds but will give you change in their own currency which can only be used in Guernsey. Also beware there maybe very long lines for the tender back to the ship we waited for over an hour for a tender. Our ship left Guernsey 11/2 hrs late because of the back up.
On the plus side this is a beautiful island. I'm so glad we were able to go. Ii know a lot of cruises lose this port due to weather, I just wish we had more time there 6 hours just isn't enough.