Dear Mr. R N Rajan
Well there are two perspectives here.
Legal: As far as my legal knowledge goes, the provisions of The Employee Provident Funds and Miscellaneous Provisions Act, 1952 are not violated by deducting the contribution on the maximum slab of Rs.6,500. There is no provision in the Act which states that the contribution amount if reduced would amount to violation of the Act.
Practical Compliance: From the compliance perspective, your case might come under the notice of the Regional Compliance Officer as the aggregate contribution would drastically come down in respect of existing employees as reflected in the ECR filed monthly. However, in order to safeguard your side, I recommend that you take a declaration from the concerned employees that they are willing to reduce the statutory contribution of both the employer and themselves, to maximimun slab of Rs.6,500. The savings thereof be added to the cash out salary, without affecting the Gross Salary
Thus, it is within your rights to reduce the contribution on Rs.6500 for existing employees.