Withdrawing Compensatory Off Credited To Employees

Dear All
Greetings of the day!
I have to withdraw Compensatory off which were credited to employees in last year because those employees just for the sake of getting a compensatory off worked on weekend while it was not that much important to work. Those leaves are being carried forward to this year also.
I have to write a formal mail to them for withdrawing those leaves from their leave balance.
Kindly help me out in drafting a proper formal mail for that.
Thanks,
N Mehta
HR Executive

Dear Mehta
Before doing anything in this regard plz discuss this issue with head of their department. May be work seems unimportant to you , could be relevant for that particular department. Before this prepare a data sheet showing these kind of event in a year and how it will help company financial as well administratively. ?
regards

Dear Amit,
Thanks for your feedback.
I have discussed this with my seniors and I am asked to withdraw those leaves. I am not finding any proper format to mail the employees.
Kindly help me on this
Thank you

Dear Nutan,
Please find the format given below.Hope that it will help you.
Dear All,
It has been noticed from muster roll that employees worked on weekly off (emploees’name and dates of weekly off on which they worked), but after discussion with dept heads/seniors it has been observed that the work was not of vital nature. And for those weekly off, compensatory off cannot be taken into consideration. This has been updated at our end for calculating this year’s leaves. Please update the same. It is also advised to work on weekly off if the work is of utmost urgent provided that working on weekly off is allowed by concern department head.
Regards
Sukhada Sant

Hi Nutan
I hope you are geared to face lot of opposition and attrition after you take this step. Why did it take you and your management 1 year to decide whether the work done was important or not? Why was this practice not stopped at that time or just after that time? WHY NOW?
As an employee, it would be natural to feel cheated and upset with the organization. I will not be surprised if you notice a sudden drop of productivity and engagement.
What you are about to do is unprofessional and damaging to the overall organization. What you should be doing is to announce a stop to this policy as of immediate effect but not touch the accrued leaves. The employees were given an opportunity to take advantage of the system and they did. That's basic human nature. So the fault is not theirs but yours and your management. If you penalize your employees for the management's shortfall then you should be geared to lose good people and lose some image.
Cheers
Navneet