How to amend comments for closed absences in per_absence_attendances

Comments for individual instances of absence can be entered by self service users but they cannot be viewed through the PUI forms. The field is not displayed on the form available in the Person=>Absence screen.

A self service user wants to a mend a comment entered previously but this function is not available for closed absence records. How can this be achieved by an administrator through the PUI?

The value is held in per_absence_attendances.comments and can be viewed via a query tool.

Any advice would be appreciated.

Thanks

Andy