Weather any public ltd company working from last 25 years can change his salary structure to reduce liability like PF Gratuity etc. It's permissible by law

One of Public Ltd. Company working from last 25 years and has Salary structure like 95% basic of gross salary, 2.5% HRA and 2.5% CCA of gross salary. But due to high basic salary company has bare more liability like PF & Gratuity. So, it is permissible by law that company change his salary structure to reduce liability. At the same time employee of company also suffer loss of PF contribution and low gratuity amount at the time of retirement. So, this type of practice can challenge by court of law ?

Section 12 of EPF act may be attracted.
Section 12 in The Employees’ Provident Funds and Miscellaneous Provisions Act, 1952
1[12. Employer not to reduce wages, etc.—No employer in relation to 2[an establishment] to which any 3[Scheme or the Insurance Scheme] applies shall, by reason only of his liability for the payment of any contribution to 4[the Fund or the Insurance Fund] or any charges under this Act or the 3[Scheme or the Insurance Scheme], reduce, whether directly or indirectly, the wages of any employee to whom the 3[Scheme or the Insurance Scheme] applies or the total quantum of benefits in the nature of old age pension, gratuity 5[, provident fund or life insurance] to which the employee is entitled under the terms of his employment, express or implied.]
If you are a worker go to labour commissioner with the complaint
If you are not a worker only remedy here could be civil litigation.

Thank you very much Mr. Nathrao for your guidance.