Disciplinary enquiry proceedings

Respected legal luminaries, I am working in a PSU. I was issued a chargesheet on 30.01.2015 on vague & baseless allegations seeking my explanation. In reply, I submitted my final explanation on 02.04.2015. After my above said explanation there was no correspondence/communication from the Disciplinary Authority for one and half years, Hence, It was understood that the Disciplinary Authority had considered my explanation satisfactorily and dropped the charges, but shockingly after 450 days,Disciplinary Authority issued me an letter wherein it is stated that “My explanation dated 02/04/2015 is not satisfactory and hence an One man committee has been constituted to enquire into the charges leveled against me” Sir, Is there no time limit for the displinary authority to decide whether my explanation is satisfactory or not or can he say that according to his choice?