Have you got a reference for this authority? If so please can you post it? Is it back dated? If it is just that the tax return has been processed and accepted, it does not mean that the IR agree to what you have written down. If this is the case, then they may well come back to you and request the money back, just as they are doing with some of my company personel regards to the cost of computers to display FCOMs on CD-ROM, email rosters, etc.