I want to reply your query in two parts viz.1) Benefit which is accepted by MoF, 2) Benefit which should be given but not accepted by the MoF
1) Your pay wll be stepped up w.r.t. your junior in terms of Note10 below Rule 7 of CCS(RP) Rules, 2008. It means any old TGT drawing less then Rs.17140/- will be stepped up to 17140/- i.e. equal to his junior. No additional benefit of previous service is given by MoF, This is the only remedy made available in such cases. This is injustice done by MoF in all cases of upgradation.
2) In all such case benefit of bunching should have been given by MoF i.e. for every two years of service one increment above Rs.17140/- should have been given. It means for eight years of service one should get 4 increments above Rs.17140/- but this has been denied by the MoF for reasons better known to them. This benefit was even allowed in 5th pay commission but this time they denied it. Later or sooner it will be given to us. Till then we could only wait.