Audit appointment for less than 5 years

As per section 139 of the Companies Act, a sole proprietor can be appointed for a term of 5 years and  a partnership firm for a period of 10 years. However, there has to be rotation of partner after 5 years. 

In the stated case, the firm can be further appointed for 3 years as it is less than 10 years. However, there has to be rotation of partners.