How to deal with lump sum rectification of underpay

I am a PAYE employee with no other incomes and earn a few thousand below the threshold where personal allowance starts to be lost. The company I work for may have been underpaying me and, if confirmed, would presumably rectify this with a lump sum payment. This would not be paid until next financial year. Having a lump sum payment in the next financial year potentially puts me well into the loss of personal allowance bracket and disadvantages me compared to if I had been correctly paid for my work during the preceding tax year in the first place. Is there a mechanism to subsequently apportion some of the lump sum in lieu of underpayment to the tax year that I worked for that money?

Hi,
Once the payment has been made, you can write in to elect to have it spread over the years it actually relates to if this is more beneficial to you.
Thank you.