Lenders will have to review the cash flow models of 10,500 companies affected by an Australian Government decision to make larger businesses pay their company tax payments monthly rather than quarterly.In a measure that pulls forward tax collections - and helps preserve the projection of a narrow budget surplus - the Government said yesterday that companies with a turnover of A$1 billion or more will be required to remit their Pay As You Go company tax instalments monthly from January 2014.Companies with a turnover of $100 million or more will have to pay monthly from January 2015. Companies with a turnover of $20 million or more will have to make monthly payments from January 2016.