This visa route is for people holding Limited leave either as:
Family life as a partner 10 year route or Family life as a parent 5 and 10 year routes
Dependant child of a person who has, or is at the same time applying for, limited leave to enter or remain in the UK other than under the points-based system or
UK Ancestry (10 year route) Private life in the UK (10 year route)
Leave outside the Rules on the basis of family or private life
If you decide to make an application under this visa route, you and any dependants included are also making a human rights claim (under the European Convention on Human Rights)
If you apply under this visa route, it is being made under section 120 of the Nationality, Immigration and Asylum Act 2002