Hello there. I am a little confused by who is and isn't going to be entitled to back payment of underpaid ESA. I understand it is mainly those migrated from IB to ESA, but I was put onto ESA from Income Support back in 2009. I was given contribution based ESA for the first year. Am I correct in thinking that because I was moved from Income Support and my/our only income was from that, then I should have instead received Income Based ESA and may therefore be entitled to some back payment?