Assessee hadn't taken a wrong credit if it had paid duty on exempted goods when dept. didn't clarify

Cenvat Credit : Where assessee asks department to clarify applicability of exemption and in absence of clarification, proceeds with payment of duty along with benefit of Cenvat credit, then, assessee cannot be said to have 'wrongly taken' credit; hence, even if said goods are later clarified to be exempted and assessee is made to reverse credit, assessee is not liable to pay interest on reversed Cenvat credit