Increase in pay : UK Payroll

Hi SAP Experts ,

I have a query and looking forward for your expert advice

My client has increase in pay from april itself but this was not implemented yet.

Now they wish to increase the Basic pay from June onwards and compensated amount of previous months to be accounted in JUNE itself.

Here mu query is that in May , outstanding amount is 35 in may and april according new pay scale.

As, these amount should be paid in JUNE only so shall I go for additional payment ( IT0015)

Can I maintain WT of salary adjustment in June for the amounts of May and April.

Kindly advice.

I also want to include that I tried this and retro occured and I got to know thet Retro pensiona claculation has also occured.(other thread for this is also there)

PLease advice me how I need to go..

Waiting for positive revert.

Thanks in advance