I e mailed P&O to find out what would be the cost of changing a return trip. I have booked now, but of course things can change and I wished to know the consequences.
Here is the reply from P&O.
Thank you for your recent communication with this office. Our fares are
calculated according to seasonal tariffs and availability and as such the
date and time of crossing is very important in calculating the final cost.
We have introduced a statutory �10.00 amendment fee and further payment may
be required to cover the difference in cost between the original sailing
booked and the crossing undertaken.
Our pricing policy has recently been changed in line with those of many low
cost airlines. The lowest fares are now made available to those customers
booking furthest in advance and at times when demand is traditionally low.
As a result the closer to your sailing date and time an amendment is made,
the higher the cost will be of that crossing.
If we can be of any further assistance, please do not hesitate to contact us
by fax on 08707 625425, or by e-mail at the following address:
customer.services@poferries.com
Basically book ahead to get a cheaper fare, and the crossing you want, but if you need to change dates made possibly a year in advance, be prepared to pay heavily.