The payment date for a payrun is determined when you set the schedule at the beginning of the year.
Before you finalise a payrun you have the opportunity to change the pay date on individual or multiple payslips.
First you need to select the payslips you want to change the payment date for.
When viewing a payrun you'll see that each entry has a checkbox next to it in the far-right column. Click the checkbox for the payslips you want to change.
If you want to change the date for all payslips then checking the box at the very top of the list will select all entries.
As soon as you select one or more payslips then a drop-down menu will appear at the bottom of the page with the title 'with x selected entries...'.
From this menu you can choose 'Change Payment Date'.
Enter your new payment date and confirm it. Your payslips will now be updated.