Andrew Sutherland

In preparing my self assessment for 23/24 I realise I misunderstood how to account for accumulating fund dividends and cash based funds and have underpaid. I have read the guidance and will contact HMRC in writing as it is from more than a year ago. Q - when I declare the imcome, I presume I also provide what type of income (dividend, etc) Do I use any numbering system (as per the original self assessment?) Q - In the original submission I depended upon HMRC to make the calculation. In making an estimate of the underpayment, is reasonable to simply use the highest tax band applied to income? I assume hmrc will recalculate accurately. Thanks.