As long as you can get off the ferry park up and complete the 9 hour rest period within 24 hours from the start of the shift you’re fine.
Bear in mind that the time it takes to get off the ferry cannot be counted as part of the 9 hours rest.
For instance if it takes 15 minutes to get off the ferry and park up you will need to have 9 hours rest plus the 15 minutes daily rest interruption.
Sent from my mobile.