(a) The retirement reserve account shall be the account from which shall be paid all annuities and benefits in lieu of annuities payable as provided in this act to retirants who retired on account of superannuation or disability and to beneficiaries of such retirants.
(b) If a disability retirant returns to teaching service:
(1) The amount of his or her accumulated contributions at the time of his or her disability retirement shall be transferred from the retirement reserve account to the members' deposit account; and
(2) The remainder of his or her annuity reserve at the time of return shall be transferred from the retirement reserve account to the employer accumulation account.