Income requirement in family immigration cases

When someone applies for family immigration, the reference person must document that they have a steady source of income. In some cases it is possible to be exempted from this requirement.
Was the application handed in before or after 9 May 2016?

By "handed in application" we mean the date the application documents were handed in at the embassy, application centre or to the police.

The rules for the reference person’s income were changed on 9 May 2016.