What is mail receipt section sa99 1du

A very specific question!

The "Mail Receipt Section" you're referring to is likely a part of the SA99 form, which is a UK-based form used to collect data on student activity and student numbers from higher education institutions.

The SA99 form is divided into several sections, and the "Mail Receipt Section" is one of them. This section is used to collect information about the number of students who have received mail from the institution, such as:

In other words, SA99.1DU is a field on the SA99 form that asks institutions to report the number of students who received mail from their institution, such as letters, emails, or other forms of communication.

This information is used by the UK's Higher Education Statistics Agency (HESA) to track student engagement and communication with higher education institutions.