Book your ferry as soon as possible! Do not delay this!
If you have a Spaceships Ferry Voucher, send in your ferry sailing dates as soon as possible. You will be issued a flexible ferry ticket so if your travel plans change you have to option to change your ferry sailing date (subject to availability).
If you prefer to book the ferry yourself, do it as soon as possible. Select a flexible ferry ticket, then you'll have the option to make changes if your travel plans change.
Book the ferry early - no matter the time of the year
Ferry disruptions are always possible. It isn't just caused by high demand in the busy summer season, it also happens in autumn, spring or winter due to weather events, scheduled maintenance or unplanned outages.
By booking your ferry ticket as early as possible you will have crossed off one item of your road trip planning list. One less item to worry about.