Section 16(4)(a) in The Khadi And Village Industries Commission Employees (Pension) Regulations, 1984
(a)An employee of the Commission who opts for clause (b) of sub-regulation (1) shall be required to refund the gratuity received in respect of his earlier service, in monthly instalments not exceeding thirty six in number, the first instalment beginning from the month following the month in which he exercised the option.