A regular client (a large organisation I have been working with for several years) sent me a payment by cheque in the post, which did not turn up on the expected date. I informed them immediately, and they chose to hang on rather than cancelling it straight away. Now it turns out the funds have cleared their account, indicating the cheque has been stolen and fraudulently cashed by a third party. The client is now saying there is no prospect of my receiving the payment until it is investigated, which could take 8 weeks, and they have given no indication that they will definitely re-issue the payment once they have confirmed it is fraud (for all I know, they may only be intending to reissue it if the bank which cashed the cheque accepts liability and refunds the money). Two questions: 1) Does merely sending out the cheque legally constitute paying me? 2) Assuming (hopefully) that the answer to the above question is no, am I entitled to kick up a fuss about the fact they are breaking the 30 day payment terms by not issuing a new cheque pending the potentially lengthy investigation?