From reading the prior year audit file you have just realised that Mason funded the original purchase of each aircraft with a secured loan carrying substantial interest charges. The loan is in the process of being renegotiated and the bank have indicated that finance costs will increase further.Furthermore, the directors have told you that Mason’s contract with the police force expires in March 20X4, at a time when the police are trying to substantially reduce the amount they pay in the wake of government cuts. It is thought that the contract will be put out to tender, and it is possible that another aircraft provider may also bid for the contract.From the above information, which is the MOST important audit risk that should be documented in the detailed audit plan?