Auditor resignation and appointment

If the Auditor who has resigned then casual vaccancy shall be appointed in his place by the Board of Directors  within 30 days  subject to approval of members within 3 months in EGM who shall hold the office till the Conclusion of AGM of the Company.

And Annual General meeting of the Company can be extended by ROC for a maximum period of 3 months. Any how AGM cannot be extended beyond 31st December. 

But if your Company is newly incorporated Company  if Incorporated before January 2017then AGM can be held within 9 months from closure of financial year i.e. maximum 31st December 2017(Only for newly incorporated Company)

And ROC on considering genuine reason can extend AGM maximum for a period of 3 months.

So Board will appoint appoint new auditor within 30 days of resignation subject to approval of shareholder within 3 months in EGM and such Auditor shall hold office till Annual General Meeting (Only for newly Incorporated Company)