As per case facts: Teachers, members of the Scheduled Tribe category, were terminated from service for purportedly securing less than the required 40% marks in their intermediate examination and for ... having invalid graduation certificates. The Department excluded marks from vocational subjects in its calculation. The appellants challenged the termination, claiming the exclusion was incorrect and that new grounds for termination (securing less than 40% based on new calculation) were introduced without a fresh notice. The question arose: whether the termination orders were proper, specifically addressing if Rule 21 of the 2012 Rules (for merit list) should apply to determine the minimum eligibility criteria (governed by Rule 4) and if the principles of natural justice were violated. Finally, the Supreme Court set aside the termination orders, holding Rule 21 was only for merit list preparation and Rule 4 for eligibility, which allowed vocational subject marks. It found the termination violated natural justice by failing to issue a fresh show cause notice on the new ground of insufficient marks and deemed the appellants in continuous service with full arrears