Each local authority ... have the duties provided for in subsection (3) in relation to a staying put arrangement.
A "staying put arrangement" is an arrangement under which—
a person who is a former relevant child by virtue of section 23C(1)(b), and
a person (a "former foster parent") who was the former relevant child's local authority foster parent immediately before the former relevant child ceased to be looked after by the local authority,
continue to live together after the former relevant child has ceased to be looked after.
It is the duty of the local authority (in discharging the duties in section 23C(3) and by other means)—
to monitor the staying put arrangement, and
to provide advice, assistance and support to the former relevant child and the former foster parent with a view to maintaining the staying put arrangement.
Support provided to the former foster parent under subsection (3)(b) must include financial support.
Subsection (3)(b) does not apply if the local authority consider that the staying put arrangement is not consistent with the welfare of the former relevant child.
The duties set out in subsection (3) subsist until the former relevant child reaches the age of 21.