At the end of the academic year/beginning of the new academic year you will need to update and re-import your spreadsheet (CSV file). You will need to remove any leavers and add any new members. All the registration groups and year groups of existing school members will need to be updated to reflect the new academic year. Once the spreadsheet is updated you will need to re-import this into Schoolcomms.
You can then delete any leavers when you no longer wish to have any further contact with them.