ok it is your call, but ! as i am "old" i have experience of meeting with tax officials /bank undermanagers/loan people when there has been a disagreement and to keep this 2nd post short , when they said "have you any proof of that" my heart sank/memory flashed back to me binning said "proof" docs,they may not entirely finalise the prob u/me /anyone may be having but they go a way to backing up your claim .and trust me on this one , it"s sods law, the day after you shread them is the day you need them.(cheery, aren"t i)