I'm no expert but is there any reason why payment can't be sent across for a certain time in the day and that it should be paid at varying times?
For instance my husbands company he subcontracts for at times the money doesn't go in until 3pm which means any direct debits due out in the morning can bounce. He gave a really convoluted explanation that his boss had told him why it can't be paid the same time each week but it doesn't seem to make any sense to me? Any ideas why this may be?