Not really, he doesnt appear to be going into all that much detail, just saying he talked to people, done his sums and compared our situation to other similar ones and he sees that as a likely figure. He's not even ventured a guess as to what the outcome of the BTC is likely to be, but I don't know the average penny in the pound settlement for a CVA involving HMRC, so it may be possible to work it out if you have that figure???