change in K code due to termination of employment

I will be leaving my current employer on the 30th April 2024. Presently I'm on a personal Tax Code of K431 due to a medical benefit valued at £4310.00, combined with my personal zero tax allowance being reduced to zero due to earnings. As I'm leaving on the 30th April, can I ask my employer to change my tax code to in effect be 1/12th of the medical benefit cost as I will only have that benefit for the single month of the financial year? I would like to inform them before they run payroll for April, rather than have to try and deal with this retrospectively. Can I do this?

Hi Adam2024,
We are for the delay in receiving your refund.
To check on the progress you will need to contact HMRC:
Self Assessment: general enquiries
Thank you.