"Someone" changed the rules in the middle of the sales transaction, now someone is going to owe the incremental cost or profit lost differential.
What profit is lost? Its an ongoing business concern and functions daily, it has not been transferred yet. With those facts known, p and o is making its profit based on its business managment decisions. There is no cost to a sale that has been cancelled by no fault of either buyer or seller, that is the commercial code. Now p and o might have a case since wps has said it will cancel its attempt to run the ports, but I highly doubt it.