As I am sure everyone would have read the terms and conditions before placing a bid, so they will be aware of what they are committing themselves to.
When it comes to winning a bid and not accepting as you are not happy with the location, they will be returned to another room in the category they had originally booked. As per the section of the T&C's below
Release of original booked Stateroom: Upon PCL accepting the Bid and sending the Upgrade Booking Confirmation, PCL will secure the upgraded stateroom for the Guest and the Guest becomes legally bound to complete payment for the price stated in the Bid. The Guest’s original booked stateroom will be released and become available for booking by any person. If the Guest fails to pay for the upgraded stateroom, PCL does not guarantee it will return the Guest to their original booked stateroom. The guest will however be returned to their original booked stateroom category.