PAYE question - Employee

Hi All, I have a couple of questions regarding the timing of PAYE earnings, please bear with me my knowledge of which is very limited. Part of my salary is paid in executive shares which can be tax advantaged (which i pay tax for through self assessment using capital gains assessment) and non tax advantaged (paid through my wages), these consist basically as the potential profit from when i am given them to me instructing the sale (minimum 3 years). Just to add at this point i work for a large UK based retail company. I have instructed the sale on 18th March for approx £42K of shares to be sold for which i made approx £23K profit and once income tax, NI & employers NI taken off gave me a payment of approx £9K with the expectation that the £23K would appear on my March payslip, the transaction was completed on 19th March. When i recieved my March payslip the payment wasnt showing and was told by payroll that the transaction would be showing on my April payslip, i asked for this to be amended back to March but was refused , my questions are below - 1 - Is it correct that a payment made to me in one tax year can appear on another tax year for taxation purposes? 2 - Would HMRC assist in putting this payment in the correct tax year? Any help on this matter is appreciated.

Hi,

Please contact our share schemes team for advice.

Employment related securities

Thank you.