In a factory kind of operation the leaves that you are presently giving is more than what is required under the law. But if you come under Kerala Shops and Commercial Establishments Act, you are expected to give 12 days' Casual Leave, 12 days of Sick leaves during a year. Each of CL and SL may be proportionately given at the rate of one per month.
However, earned leave is admissible only to employees who have completed 12 months of service and the total earned leave is 12 days. In order to bring a common date january 1st) for crediting the leaves to all employees across the organisation, it is advisable to give EL to those who have joined during the preceding year proportionately to the months worked in the preceding year. This adjustment is acceptable even for the law enforcing officers.
Granting EL only to permanent employees is not acceptable but it should be given to all employees whether permanent or temporary if they have worked for 12 months. Therefore, if you do not want that a probationer be given EL, you can hold it for 12 months and you need not credit the EL of probationers pro rata basis in January. But as soon they complete 12 months, you should credit 12 days EL.
Under the labour law, any person engaged to do any work connected with the business of the organisation is an employee. All such employees are required to be given all social security benefits and employee benefits like hours of work, intervals of rest, weekly off, leave with wages etc. There is no classification called temporary and permanent for treatment of granting of leave with pay. You can terminate employment of a probationer without notice, there is no lien on employment for a temporary employee and that he cannot demand permanency. But you cannot refuse to give leave, or you cannot ask him to work for more than 8 hours a day or 48 hours a week, or you cannot ask him to work continuously for more than 10 days. Though paying overtime wages or granting compensatory holidays are remedies but you cannot demand such working.