Special provision with respect to payment of bonus linked with production or productivity.

31A. Notwithstanding anything contained in this Act,—

(i) where an agreement or a settlement has been entered into by the employees with their employer before the commencement of the Pay­ment of Bonus (Amendment) Act, 1976 (23 of 1976), or

(ii) where the employees enter into any agreement or settlement with their employer after such commencement,

for payment of an annual bonus linked with production or productivity in lieu of bonus based on profits payable under this Act, then, such employees shall be entitled to receive bonus due to them under such agreement or settlement, as the case may be :

Provided that any such agreement or settlement whereby the employees relinquish their right to receive the minimum bonus under section 10 shall be null and void insofar as it purports to deprive them of such right:

Provided further that such employees shall not be entitled to be paid such bonus in excess of twenty per cent of the salary or wage earned by them during the relevant accounting year.