It could be fraud by false representation (i.e. falsely representing to the bank that it was a legitimate and intended transfer the account holder was expecting

It could be fraud by false representation (i.e. falsely representing to the bank that it was a legitimate and intended transfer the account holder was expecting to receive) per S2 of the Fraud Act 2006, but it's typically easier to prove theft under S1 of the Theft Act 1968 since that doesn't require any false statement to be made.