1. As per sec 44AB in case of a person who is engaged in the profession if his gross receipts exceed Rs. 50 lakhs during the year, he is required to carry out tax audit mandatorily.
2. In your case doctor is a profession and since gross receipts exceed Rs. 50 lakhs tax audit as per sec 44AB is compulsory. The time limit for filing a return will be 30.09.2019.
Please correct me if the above solution has an alternative view.