Australian here. I've transferred booking from one cruise to another with payment of $100 pp fee. Refund? Nope.
As per this.
31. Changing your booking
Subject to clause 29 (Price changes) and availability, some changes (excluding changes to ship or sailing date) can be made to your booking. You may request changes via your travel agent up to 45 days before departure. We will make every effort to meet your change request; however, we cannot guarantee that we will be able to make any requested change. Please note: any booking that is modified after the promotion has ended will result in the loss of the promotion. Examples of changes that will result in the promotion being forfeit are including, but not limited to; change of ship, sail date, category booked, amending the travel agency ID or selecting an alternate price/promotion. Up to 45 days before departure an administration fee of AU$50 per booking will be payable for each change requested. If you request a change within 45 days of departure, this will be treated as a cancellation of your original booking and cancellation charges as set out in these terms and conditions will be payable. The changed arrangements will then be treated as a new booking.
If you book a promotion cruise which stipulates that the deposit is non-refundable, a change fee of AU$100 per person per change will apply up to 151 days prior to departure. Inside of 150 days, ticket contract cancellation conditions will apply.