JUDGMENT Nelson Sailo, J. - This order will disposed of all the three (3) writ petitions since common questions and identical issues are involved. 2. Heard Mr. A.R. Malhotra, learned counsel for the petitioners in WP(C) Nos. 98 & 102/2018 and Ms. Vanlalhriati, learned counsel for the petitioners in WP(C) No. 100/2018. Also heard Mr. L.H. Lianhrima, learned Senior Counsel assisted by Ms. Ruth Lalruatfeli, learned counsel for the respondent Nos. 5 to 29 in WP(C) No. 98/2018 and for the respondent Nos. 5 to 26 in WP(C) No. 100/2018. I have also heard Mrs. Linda L. Fambawl and Ms. Mary L. Khiangte, Govt. Advocates for the State respondents in all the writ petitions. 3. The dispute involved in these writ petitions is with regard to interse-seniority between the petitioners and the private respondents in the Senior Grade of the Mizoram Engineering Service (MES for short). In WP(C) Nos. 98 and 100 of 2018, the dispute on seniority is between Graduate Engineers while in WP(C) No. 102 of 2018, it is between the Diploma Engineers. The facts set out in WP(C) No. 98 of 2018 are being narrated for the sake of brevity and convenience. 4. The case of the writ petitioners is that the respondents on account of stagnation of Engineers in the Junior Grade of the MES came up with a Notification dated 04.08.2015 (Annexure-3), wherein it was provided that Engineers in the Junior Grade of the MES will be allowed Non-Functional up-gradation to the Grade Pay of Rs. 6,600/- subject to completion of unblemished continuous service for at least 10 years in the Junior Grade. On such up-gradation, they will be designated as Senior Sub-Divisional Officer/Senior Assistant Engineer. Besides this, any member of the Junior Grade of the MES who have already availed the Second Stage in the MACP, 2010 shall be deemed to have been upgraded on Non-Functional basis to the Senior Sub-Divisional Officer/Senior Assistant Engineer Grade. In fact, Notification dated 04.08.2015 was issued in exercise of the powers conferred by the proviso to Article 309 of the Constitution of India. 5. In continuation to the Notification dated 04.08.2015, a Screening Committee was constituted to consider eligible Junior Engineers for NonFunctional up-gradation vide Notification dated 12.08.2015 (Annexure-4). In fact, Notification dated 04.08.2015 was issued in exercise of the powers conferred by the proviso to Article 309 of the Constitution of India. 5. In continuation to the Notification dated 04.08.2015, a Screening Committee was constituted to consider eligible Junior Engineers for NonFunctional up-gradation vide Notification dated 12.08.2015 (Annexure-4). Besides constituting a Screening Committee through the said Notification, a bench mark for such up-gradation as prescribed under paragraph 3.5 (i) of the DPC guidelines issued vide Office Memorandum dated 15.07.2010 was also notified. Paragraph 3.5 (i) of the Office Memorandum provides that "Very Good ? shall be the bench mark for Group-A and Group-B Gazetted posts while "Good ? shall be the bench mark for Group-B and Group-C posts. 6. While up-gradation of the Junior Engineers of the MES including the petitioners were being considered, a clarification was sought by the Deputy Secretary, Public Works Department (PWD) from the Department of Personnel & Administrative Reforms (General Service Wing) [DP&AR (GSW)] (respondent No. 3) vide communication dated 27.08.2015 (Annexure-6). The Under Secretary, DP&AR vide ID No. A 12018/28/2013- P&AR (GSW) dated 06.10.2015 (Annexure-7) while giving the clarification also informed the PWD that the eligibility criteria for promotion to Senior Grade of the MES as per Rule 22(5) of the Mizoram Engineering Services Rules, 2013 (Rules of 2013) should be duly followed irrespective of the reservation for Graduate and Non-graduate Engineers. 7. Rule 22(5) of the Rules of 2013 provides that vacancies in the Senior Grade is to be filled up from members in the Junior Grade who have completed not less than 5 years continuous regular service in the grade and who have passed Departmental Examinations in Engineering and Accounts. According to the petitioners, such was not the requirement as per Notification dated 04.08.2015 and therefore, it cannot be introduced by way of administrative instruction since Notification dated 04.08.2015, was issued in exercise of their powers conferred by the proviso Article 309 of the Constitution of India. 8. Consequently, in view of the clarification, the petitioners have been up-gradated to the Grade of Senior Assistant Engineer/Sub-Divisional Officer only from the date they passed the Departmental Examination and their seniority in the Senior Grade of the MES (Civil) (Direct & Promotees) under the PW Cadre has been fixed as per the date on which they passed the Departmental Examination. Consequently, in view of the clarification, the petitioners have been up-gradated to the Grade of Senior Assistant Engineer/Sub-Divisional Officer only from the date they passed the Departmental Examination and their seniority in the Senior Grade of the MES (Civil) (Direct & Promotees) under the PW Cadre has been fixed as per the date on which they passed the Departmental Examination. As a result, the Engineers who were otherwise junior to the petitioners as per the final inter-se-seniority of Assistant Engineer/Sub-Divisional Officer which was finally fixed vide Office Memorandum dated 02.06.2015 have been placed well above them. 9. Mr. A.R Malhotra, the learned counsel submits that when the State respondents have permitted Non-Functional up-gradation of the Junior Grade of the MES with the criteria that the members of the Junior Grade should have completed unblemished continuous service of at least 10 years in the Junior Grade vide Notification dated 04.08.2015, the same cannot be varied to the disadvantage of the petitioners by way of administrative instruction. He further submits that the State respondents have subsequently come up with an amendment of the Rules of 2013 by framing the Mizoram Engineering Services (Amendment Rules of 2017) (Rules of 2017) wherein, Sub-clause (b) has been inserted against Rule 22(5) incorporating the necessity of having passed Departmental Examination besides having 10 years of continuous regular service in the Junior Grade in order to be considered for Non-Functional promotion to the next higher grade. He submits that the framing of the Rules of 2017 which came into force only w.e.f 30.11.2017 cannot take away the accrued rights of the petitioners as provided by the Notification dated 04.08.2015 and much less, by issuance of the administrative instruction vide the clarification communicated to the Department on 06.10.2015. Therefore, the petitioners have every right to be upgraded w.e.f 04.08.2015 since they already completed 10 years of continuous service in the Junior Grade. In this connection, the learned counsel relies upon the decision of the Apex Court rendered in the State of Haryana Vs. Samsher Jang Bahadur, (1972) 2 SCC 188 , wherein, it was held that the Government cannot alter the rules framed under the proviso to Article 309 of the Constitution of India by way of administrative instruction. In this connection, the learned counsel relies upon the decision of the Apex Court rendered in the State of Haryana Vs. Samsher Jang Bahadur, (1972) 2 SCC 188 , wherein, it was held that the Government cannot alter the rules framed under the proviso to Article 309 of the Constitution of India by way of administrative instruction. He, therefore, submits that the consequential steps taken by the respondent authorities pursuant to the clarification issued on 06.10.2015 by the respondent No. 3 should be interfered with by this Court. 10. The learned counsel further submits that the petitioners realizing that they will be deprived of the benefit of being upgraded as per Notification dated 04.08.2015 by restricting their up-gradation only w.e.f the date of passing the Departmental Examination approached the respondent authorities by filing representations. However, their representations have been rejected by the respondent No. 3 vide Communication under ID No. B. 11015/1/2012-P&AR (GSW) dated 26.07.2018 (Annexure-15), wherein, it was stated that the inter-seseniority of officers in the Senior Grade of the MES within the direct and promotion quota in each Wing of the PW Cadre be fixed separately by taking into consideration the order of merit as recommended by the respective Departmental Promotion Committee or Departmental Screening Committee. The recommendation of the Departmental Screening Committee for the up-gradation of the petitioners, being an up-gradation only from the date of passing the Departmental Examination, the petitioners have no alternative but to approach this Court through the present writ petition. 11. The learned counsel further submits that the State respondents lately have come up with a provisional inter-se-seniority list of the Senior Grade of the MES (Civil) (Direct & Promotees) under the PW Cadre vide Notification dated 10.08.2018. Although an opportunity to file representation by any officer aggrieved is provided, the same is only an empty formality as inasmuch as the respondents have already taken a decision to act upon the clarification given by the respondent No. 3 on 06.10.2015. 12. Mr. A.R. Malhotra, learned counsel for the petitioners submits that there is difference between functional and non-functional promotion. 12. Mr. A.R. Malhotra, learned counsel for the petitioners submits that there is difference between functional and non-functional promotion. As per the provisions of Rule 22 (5) of the Rules of 2013, a member of the MES in the Junior Grade who has completed not less than 5 years of continuous regular service in the Grade and have passed Departmental Examination in Engineering and Accounts conducted by the Mizoram Public Service Commission (MPSC) is eligible to be considered for promotion by a selection method. The said provision also provides for 80% reservation of the post for Graduate Engineers and 20% for NonGraduate Engineers. Whereas, in terms of the Notifications dated 04.08.2015 and 12.08.2015, a member of the MES who has completed unblemished continuous service of at least 10 years in the Junior Grade is eligible for Non-Functional up-gradation to the Grade Pay of Rs. 6,600/- and on such upgradation, he shall be designated as Senior SDO/Senior AE. There is no stipulation or requirement to pass the Departmental Examination in Engineering and Accounts. As per the Notification dated 12.08.2015, the effective date of implementation of the up-gradation is fixed as 04.08.2015 and the actual monetary benefit is also to be given from that date. The member of the MES to be considered by the duly constituted Screening Committee should have the required bench mark for up-gradation as prescribed under paragraph 3.5(i) of the Office Memorandum dated 15.07.2010. He submits that the petitioners were duly screened as per the criteria laid down by the two (2) Notifications and therefore, there is no reason as to why they should not be given seniority w.e.f. 04.08.2015. The Notification dated 04.08.2015 having been issued under the powers conferred by the proviso to Article 309 of the Constitution of India, the clarification issued by the respondents in the DP&AR(GSW) on 06.10.2015 by way of an executive instruction cannot prevail over the former notification. Under the circumstance, seniority list of the Senior Grade of the MES should be redrawn by counting the seniority of the petitioners w.e.f. 04.08.2015. 13. Mr. L.H. Lianhrima, learned Senior Counsel by referring to the Notification dated 04.08.2015 submits that the expression "unblemished continuous service of at least 10 years in the Junior Grade? would definitely mean that the members of the MES should have passed Departmental Examination in Accounts and Engineering. 13. Mr. L.H. Lianhrima, learned Senior Counsel by referring to the Notification dated 04.08.2015 submits that the expression "unblemished continuous service of at least 10 years in the Junior Grade? would definitely mean that the members of the MES should have passed Departmental Examination in Accounts and Engineering. While the private respondents he represents cleared the Departmental Examination on the two (2) subjects, the petitioners on the other hand, did not bother to clear the exams in time. Accordingly, their seniority has been counted rightly from the date they passed the Departmental Examination. 14. The learned Senior Counsel has further drawn the attention of this Court to the term "Senior Grade ? as given in paragraph No. 3 of the impugned Notification of the DP&AR (GSW) dated 06.10.2015. He submits that the term "Senior Grade? implies the Senior Grade of the MES and that the members of the MES are governed by the Rules of 2013, which clearly prescribes passing of the Departmental Examination in order to be considered for promotion to the Senior Grade of the MES from the Junior Grade. Therefore, the Notifications dated 04.08.2015 and 12.08.2015 are to be read together with the Rules of 2013 and not separately. A conjoint reading of both the provisions clearly goes to show that passing of Departmental Examination is mandatory. 15. The learned Senior Counsel has also drawn the attention of this Court to Rule 5(ii) of the Rules of 2013, which provides that the service should also include any post or grade subsequently included in the cadre of the service. In view of this provision, the post designated as Senior SDO or Senior AE in terms of Notification dated 04.08.2015 will also be included as post under the MES. As such, passing of Departmental Examination in order to be promoted to the next higher grade is mandatory. The learned Senior Counsel further submits that the clarification given in the Communication dated 06.10.2015 does not attract the case of State of Haryana Vs. Samsher Jang Bahadur (supra) as contended by the counsel for the petitioners inasmuch as, the said clarification is only an reiteration of the relevant provisions of the MES Rules, 2013 and not a separate executive or administrative instruction by itself. Samsher Jang Bahadur (supra) as contended by the counsel for the petitioners inasmuch as, the said clarification is only an reiteration of the relevant provisions of the MES Rules, 2013 and not a separate executive or administrative instruction by itself. The learned Senior Counsel thus submits that the MES Rules of 2013 was in operation since it was framed and it did not cease to operate between 04.08.2015 to 30.11.2017 as claimed by the petitioners. Under the circumstance, he submits that there is no merit in the writ petitions and the same should be dismissed. 16. Mrs. Linda L. Fambawl and Ms. Mary L. Khiangte, learned Govt. Advocates appearing for the State respondents also adopt the argument of Mr. L.H. Lianhrima, learned Senior Counsel. They further submit that the provisions of the Rules of 2013, its amendment, Notification dated 04.08.2015 and the Clarification dated 16.10.2015a are all complimentary to each other. A conjoint reading of the above Rules and Notifications clearly goes to show that passing of the Departmental Examination in Engineering and Accounts is essential for promotion to the Senior Grade of the MES since the commencement of the MES Rules of 2013 w.e.f. 23.09.2013 and that the same does not cease to operate even between the period 04.08.2015 to 30.11.2017. Under the circumstance, they submit that the writ petitions have no merit and should be dismissed. 17. I have heard the submissions made by the learned counsels for the rival parties and I have perused the materials available on record. From the projection made by the parties, the issue to be considered is as to whether the seniority of the petitioners should be counted w.e.f 04.08.2015 or w.e.f the date they have passed the Departmental Examination in Accounts and Engineering as adopted/accepted by the official respondents. For better understanding of the issue under consideration, Rule 22(5) of the MES Rules of 2013 may be abstracted hereunder : "(5) Senior Grade : Pay Band 3 in the scale of Rs. 15,600/- Pay 39,100/- with Grade Pay Rs. 6,600/- p.m. To fill up vacancy(ies) in this Grade, members of the Service in the Junior Grade who have completed not less than 5 years continuous regular service in the Junior Grade and have passed Departmental Examinations in Engineering and Accounts conducted by the Mizoram Public Service Commission shall be eligible for consideration for promotion by Selection Method. 6,600/- p.m. To fill up vacancy(ies) in this Grade, members of the Service in the Junior Grade who have completed not less than 5 years continuous regular service in the Junior Grade and have passed Departmental Examinations in Engineering and Accounts conducted by the Mizoram Public Service Commission shall be eligible for consideration for promotion by Selection Method. Provided that 80% of the posts shall be reserved for Graduate Engineers and 20% for Non-Graduate Engineers. Page 14 of 17 Provided further that the reservation system shall be discontinued after all the present incumbent NonGraduate Engineers in Junior Grade as on the date of commencement of these rules get promotion, dead, retired or quitted the Service by any means." 18. From the above abstract, it may be seen that in order to be eligible for promotion from the Junior Grade of the MES to the Senior Grade of the MES, the Officer concerned should have completed not less than 5 years of continuous regular service in the Junior Grade and should have passed Departmental Examination in Engineering and Accounts conducted by the MPSC. 19. Further, it is the stand of the official respondents that in view of the stagnation of the members of the MES in the Junior Grade, a decision was taken by the Council of Ministers in its meeting held on 23.07.2015 to allow Non-Functional up-gradation to members of the Junior Grade of the MES on certain terms and conditions. Pursuant thereto, a Notification dated 04.08.2015 was issued by the Secretary to the Govt. of Mizoram, DP&AR (GSW) notifying that the Governor of Mizoram in exercise of the powers conferred by the proviso to Article 309 of the Constitution of India was pleased to allow Non-Functional up-gradation to members of the Junior Grade of the MES to the Grade Pay of Rs. 6,600/- subject to completion of unblemished continuous service of at least 10 years in the Junior Grade and on such up-gradation, the designation would be Senior SDO/Senior AE. In the Notification dated 12.08.2015 notified soon thereafter, the effective date for implementation of Non-Functional up-gradation was fixed as 04.08.2015 and from which date, the actual monetary benefit would also be given. Further, a Screening Committee as mentioned in the said Notification was also constituted and also the bench mark for such up-gradation prescribed as was given under paragraph 3.5(i) of the Office Memorandum dated 15.07.2010. Further, a Screening Committee as mentioned in the said Notification was also constituted and also the bench mark for such up-gradation prescribed as was given under paragraph 3.5(i) of the Office Memorandum dated 15.07.2010. Besides the aforementioned requirements, there appears to be no other stipulation including the requirement to pass the Departmental Examination as given in the MES Rules of 2013. As already stated, Rule 22(5) of the MES Rules of 2013 provides for Functional promotion from Junior Grade to Senior Grade of the MES whereas, the Notifications dated 04.08.2015 and 12.08.2015 provides for Non-Functional up-gradation subject to the member of the MES fulfilling the criteria prescribed therein. 20. From a plain reading of the two (2) Notifications, it is clear that there is no requirement for one to pass Departmental Examination in order to be considered and given Non-Functional promotion from Junior Grade to Senior Grade. This can be clearly appreciated from the fact that the requirement to pass Departmental Examination in order to be given Non-Functional promotion from Junior Grade to Senior Grade of the MES only came to be prescribed in the MES Rules of 2017, which came into force w.e.f. 30.11.2017. This would therefore go to show that there was no stipulation for passing of the Departmental Examination in Accounts and Engineering in order to get promotion on Non-Functional basis for the period between 04.08.2015 to 30.11.2017. The admitted position is that all the petitioners have been screened by the constituted Screening Committee and thereafter, they were given Non-Functional promotion but only from the date of passing the Departmental Examination. There can be no argument with the well settled principle of law that administrative or executive instruction cannot override the statutory provision of law and that it is only where the statute is silent that such administrative or executive instruction can be invoked to compliment and not override the statute. The clarification of the DP&AR(GSW) dated 06.10.2015 impugned by the petitioners in my considered view is not an executive or administrative instruction but merely a reiteration of the provisions of Rule 22(5) of the Rules of 2013 as rightly pointed out by Mr. L.H. Lianhrima, learned Senior Counsel. However, the fact remains that the petitioners were given Non-Functional promotion to the Senior Grade of the MES in terms of the Notifications dated 04.08.2015 and 12.08.2015. L.H. Lianhrima, learned Senior Counsel. However, the fact remains that the petitioners were given Non-Functional promotion to the Senior Grade of the MES in terms of the Notifications dated 04.08.2015 and 12.08.2015. Therefore, Rule 22(5) of the Rules of 2013 which provides for Functional promotion will have no application to their case. 21. In view of above and upon due consideration of the case in its entirety, I find substance in the grievance of the petitioners. Accordingly, all the three (3) writ petitions are disposed of with a direction to the State respondents to give the petitioners the benefit of counting their seniority in the Senior Grade of the MES w.e.f. 04.08.2015 as per the Notifications dated 04.08.2015 and 12.08.2015. Consequently, the impugned provisional seniority list stands interfered with and the official respondents are directed to redraw the same in terms of the observation and finding arrived at herein above within a period of six (6) weeks from the date of receipt of a certified copy of this Order. 22. All the interim orders passed earlier shall stand merged with this order. No cost.