Uploading Documents to Myepaywindow

When uploading a document from a 3rd party system to either Employee Document or Other, on the employee record in Myepaywindow, these documents auto delete after 3 months.

We would like to be able to control this internally, but there is currently no option in the Administration functions. We have uoploaded P11D's produced in a 3rd party system and were not made aware that they would delete, 3 months after loading. We would like to be able to customise the settings, to suit individual clients, but also we would not want a P11D document deleteing during the workers employment period.