The Department is correcting some past underpayments of ESA that arose when people moved from incapacity benefit on to ESA. We realise how important it is to get this matter fixed. Clearly, the mistakes should never have happened, but we know that it is vital that it is sorted as quickly as possible. Last Thursday, I tabled a written statement that updated the House on progress since the previous written statement in October last year. We are on track to complete work on the majority of the original 320,000 cases by the end of April this year. As of 11 February, 310,000 of that overall number have started the reassessment journey. We have paid arrears of over £328 million to 58,000 people, which is significant progress. The Department has also increased the number of staff working on putting these cases right from about 400 staff to approximately 1,200 staff, which will enable us to continue to complete this important activity at pace.

Following the announcement in July last year to pay cases back to the point of conversion, I confirmed in October that this will require us to review an additional 250,000 cases. We have started this activity and will aim to complete this phase by the end of the year. Last Thursday, the Department published an ad hoc statistical publication on gov.uk that sets out further detail on the progress it has made on processing the cases, including an updated estimate on forecast expenditure and the number of people affected. The Department now estimates that about 600,000 cases require review and that by the end of the exercise about 210,000 arrears payments will have been made. The increase, compared with the previous estimate of 180,000, is based on additional sampling and very careful, thorough checking. Alongside the written statement that was published last Thursday, I also published an updated version of the frequently asked questions, and this has been deposited in the House Library.