Works underpaid partner will his backpay affect UC

ksjm04

hi,

So today my partner who works we have a joint uc claim. He found out today his work have underpaid him for almost 3 years as when he was given a new position he should of been receiving a higher amount they failed to tell him this he wasn’t aware but its on his contract and they admitted fault and plan to pay it in a lump sum along with his next wage.

can someone tell me how will this affect our UC each month now? Will they stop paying us? Tell us we have been overpaid? Or take it as he just made a large amount that month so we will get zero for a month then back to normal when he gets his usual earnings the next month?

the amount he is owed from work is around £5,000.

Thank you