(1) Once a year during the first five (5) years following retirement of a member on either duty or non-duty disability retirement allowance, and once in every three-year period thereafter, the board may require any disability beneficiary who has not completed twenty (20) years’ service under the terms and provisions of this article to undergo a medical examination at the place of residence of the beneficiary or other place mutually agreed upon, to be made by a physician or physicians designated by the board. Should any disability beneficiary who has not completed twenty (20) years’ service under the terms and provisions of this article refuse to submit to at least one (1) medical examination in any such year by a physician or physicians designated by the board, his allowance shall be discontinued until his withdrawal of such refusal, and should his refusal continue for one (1) year, all his rights in and to any and all retirement allowances under the retirement system shall be revoked by the board.

(2) Should the examining physician or physicians report and certify to the board that a disability retirant has recovered and is able to engage in a gainful occupation, and should the board concur in such report, then the disability retirement allowance shall cease. In the case of a duty disability retirant only, upon again becoming an employee of the employer, he shall again become a member of the retirement system and the time during which he was a disability retirant shall be counted as time in the service of the employer for the purpose of service retirement.

(3) Any disability retirant, who has not completed twenty (20) years’ service under this article prior to retirement, who secures gainful employment over a period of three (3) consecutive months shall not thereafter receive any disability retirement allowance and it shall be the duty of the board to revoke its order directing the payment of a retirement allowance to such person.