A person shall, so long as he is, and for twelve months after he ceases to be, a member of a local authority F2in England, be disqualified for being appointed F3or elected by that authority to any paid office, other than to the office of chairman or vice-chairman F4or, in the case of a local authority F2in England which are operating executive arrangements which involve a leader and cabinet executive, the office of executive leader or member of the executive. . ..