12. The OM dated 21.08.2015, which contains a clause for extending the medical facilities that were being availed by serving employees; leaves some scope for interpretation. After a careful reading of OMs dated 20.03.2018 and 13.03.2019, it is unequivocal that the master OM on the issue of extending medical facilities to retired employees of KVS is the one, which was issued on 21.08.2015. After glancing through this OM, it is nowhere found that it speaks about the extension of CGHS facilities to the retired employees of KVS, who were having such facilities while in service. This condition is added only in the OM dated 13.03.2019, which, in our opinion, is not at all issued in supersession of OM dated 21.08.2015. In fact, in all the OMs referred to above, it is clearly mentioned that the terms and conditions contained in OM dated 21.08.2015 will remain unchanged, meaning thereby the tone and tenor of the OM dated 21.08.2015 remains intact. More so, the OM dated 13.03.2019, nowhere speaks that it would be applicable from retrospective effect.”