JUDGMENT : The petitioners in these writ petitions are employees of Jawaharlal Nehru Tropical Botanic Garden & Research Institute, a research institute working under the Kerala State Council for Science Technology and Environment. 2. The grievance of the petitioners in these writ petitions is that without amending the service rules of the respondent institution, the casual leave has been reduced from 20 days to 8 days. The submission is that the service rules provide for casual leave and by an executive order or decision without amending the service rules, the casual leave could not have been reduced from 20 days to 8 days. 3. There cannot be any quarrel or dispute with the proposition that the service benefit conferred by the statutory prescription cannot be taken away by an executive decision. However, the question that needs to be considered in these writ petitions is whether the service rules have been amended and if they have been amended when they have been amended. 4. There are 11 institutions which are working under the Kerala State Council for Science Technology and Environment, which is the Apex body. In respect of the Scientists, the apex body follows the service benefits as conferred by the CSIR on its employees where 5 days working in a week and casual leave of 8 days are admissible to the employees / Scientists. 5. Since there were two sets of working days and casual leave, the apex society, vide the decision of the Annual General Body dated 15.11.2018, to amend the service rules and provide for the casual leave of eight days to all the employees with five working days in a week. In pursuance to the said decision of the General Body dated 15.11.2018, the rules could be amended only on 29.11.2019 and the amended rule would read as under:- Section II Part I Clause 11.1.1 is submitted as follows: “Casual leave admissible shall be on the rate of 20 days in a calendar year for the employees of those institutions which are following six day week working pattern subject to the condition that the total period of absence on casual leave combined with holidays shall not exceed 15 days at a time and for the employees of those institutions which are following five day week working pattern, casual leave admissible shall be at the rate of 8 days in a calendar year. This amendment will come into force with immediate effect.” 6. When the service rule stands amended of the petitioners and other employees providing for casual leave for 8 days and working of 5 days in a week, the petitioners and other employees could be entitled for 8 days casual leave with effect from 29.11.2019, the date when the rules got amended. 7. The grievance of the petitioners is that without amending the relevant service rules by executive order, the service benefit conferred on them was reduced no longer in view of the amendment brought in the service rule with effect from 29.11.2019. In view thereof, all these writ petitions are disposed of, with a declaration that the petitioners and other employees working under Kerala State Council for Science Technology and Environment shall be entitled to 8 days casual leave with 5 days working in a week. The interim order, if any, in these writ petitions shall stand vacated, and the pending interlocutory application shall stand closed.