18.—(1) A person in eligible service who is not in pensionable service under this scheme may opt to become an active member of this scheme in relation to that eligible service.
(2) The option under this regulation may only be exercised by written notice to the scheme manager (“opt-in notice”).
(3) The option under this regulation is taken to be exercised on the date on which the opt-in notice is received by the scheme manager(1).
(4) If P opts out of this scheme within 12 months after opting in, P may not opt in again until after the end of that period of 12 months.
(5) A person who was in pensionable service before beginning a career break or any other period of unpaid leave is taken to re-enter pensionable service when returning from the career break or other period of unpaid leave.
See regulation 19 for when an opt-in has effect.