ONE MACP is adjusted against TWO PROMOTIONS - Unique anomaly

In our Department (Central Excise), we have Tax Assistant (Rs.2400 Gpay) and its promotional post Senior Tax Assistant (4200 Grade pay) & its promotional post - Deputy office Supdt. (Rs.4200 Gpay with 3% Increment).   Then Dy. Office Supdt. gets promoted to Admn. Officer (4600 Gpay).

One situation is:  

A few Senior Tax Assistants in Rs.4200 Grade pay have been granted MACP to 4600 Grade pay prior to promotion to Dy. Office Supdt.   Then they have been promoted as Dy. Office Supdt.   As MACP already granted, no fixation on promotion.    After some years as Dy. Office Supdt., they have been promoted as Admn. Officers (Rs.4600 Grade pay).   Hence, no fixation.   Here, one MACP of Rs.4600 Grade pay is adjusted against 2 Promotions.

MACP envisages placement in the next immediate higher grade pay.   Hence, a Tax Assistant drawing Grade pay of Rs.2400 is placed in Rs.2800 Grade pay.   Then on promotion as senior Tax Assistant, he is granted Rs.4200 Grade pay.   Likewise, a Senior tax Assistant (Rs.4200 Grade pay) is given Rs.4600 Grade pay on MACP.      (Only Rs.5400 gpay in PB2 & PB3 have been mentioned to be different Grade pays as per Para 8.1 of MACP Order).    As 3% increment (illogical) order dt.7.1.2013 has been issued & made applicable to Rs.4200 grade pay posts (feeder and promotional), a Senior Tax Assistant is drawing lesser Grade Pay on Promotion than on MACP which is a great anomaly.  
   
I have been fighting the case of Grade pay in the Hon`ble CAT, Chennai Bench which is in final stages.     Hope to get positive verdict on this sooner.