You have to peruse the appointment letter and the clauses printed therein. If the present change is affecting your career and future employment prospects, it is better to represent and record your strong objections to the competent authority through proper channel.
If this representation fails to invoke proper response from the competent authority and if you do not get the relief sought, you may approach CAT after exhausting the remedies available in the lower level.
A proper discussion at length with the an expertise service law practicing lawyer in your locality would suggest you more ideas about how to handle the situation and what can be done next and how to get the solace. Approach one.