Seniority list

This is regarding defence estates organisation. the technical post here are as under ADEO Gazzeted post for degree/ diploma with 3 yr exp in civil engineering GP 4600, 20% direct and 80% promotion after 3 year service from SDO-I. SDO-I for degree/ diploma with 3 year exp in civil engineering GP 4200, 20% direct and 80% promotion after 3 year service from SDO-II. SDO-II GP [deleted]% promotion from SDO-III after 5 year service. SDO-III for ITI GP 2800 only direct recruit. i hemant have joined department on 10.05.2010 as SDO-I on GP 4200 further promoted in yr 2015 as ADEO. now doing work as ADEO. rakesh who is SDO-III got promoted in SDO-II on 24.08.2009. and further continue do the service as SDO-II. as on 10.05.2010 hemant is senior in department than rakesh. department suddenly vide letter dt. 11.02.2016 merged the post of SDO-II with SDO-I and redesignated as SDO-I GP 4200 as per recommendation of 6th pay commission and DOPT order no. 20020/4/2010-Estt.(D) dt 13.09.2012 and further issued draft seniority list in which department placed rakesh as SDO-I from 24.08.2009 on the date of promotion as SDO-II while hemant consider as SDO-I from 10.05.2010. is it relevant while hemant have already given service more responsible sit. kindly mention the relevant supreme court order or DOPT order from which i could fight my case.