A reference to Industrial Disputes Act will be informative
Industrial Disputes Act, 1947
19.Period of operation of settlements and awards
(1) A settlement 110[* * *] shall come into operation on such date as is agreed upon by the parties to the dispute, and if no date is agreed upon, on the date on which the memorandum of the settlement is signed by the parties to the dispute.
(2) Such settlement shall be binding for such period as is agreed upon by the parties, and if no such period is agreed upon, for a period of six months 104[from the date on which the memorandum of settlement is signed by the parties to the dispute], and shall continue to be binding on the parties after the expiry of the period aforesaid, until the expiry of two months from the date on which a notice in writing of an intention to terminate the settlement is given by one of the parties to the other party or parties to the settlement.
111[(3) An award shall, subject to the provisions of this section, remain in operation for a period of one year 112[from the date on which the award becomes enforceable under section 17A]:
PROVIDED that the appropriate government may reduce the said period and fix such period as it thinks fit:
PROVIDED FURTHER that the appropriate government, may, before expiry of the said period, extend the period of operation by any period not exceeding one year at a time as it thinks fit so, however, that the total period of operation of any award does not exceed three years from the date on which it came into operation.