The members of the Council shall hold and vacate office in accordance with their terms of appointment, subject to the following provisions.
. . .
A person shall not be appointed to the Council for a term exceeding five years, but previous membership does not affect eligibility for re-appointment.
A member may at any time resign his membership, and the chairman or a deputy chairman may at any time resign his office as such, by notice in writing to the Secretary of State.
If the Secretary of State is satisfied that a member—
has been absent from meetings of the Council for a period longer than six consecutive months without the permission of the Council, or
has become bankrupt or has had a debt relief order (under Part 7A of the Insolvency Act 1986) made in respect of him or has made an arrangement with his creditors (or, in Scotland, has had his estate sequestrated or has made a trust deed for his creditors or has made and had accepted a composition contract), or
is incapacitated by physical or mental illness, or
is otherwise unable or unfit to discharge the functions of a member,
the Secretary of State may declare his office as a member to be vacant and shall notify the declaration in such manner as he thinks fit, whereupon the office shall become vacant.