Regarding appointment of auditors

As per section 141 of the Companies Act 2013, an auditor is to be removed for the AGM ending 2017 in case it continues as a Proprietory concern for more than 5 years and 10 years in case of a firm consecutively as on the date of commencement of the Companies Act 2013. My query is a person whereas completed more than 5 years and afterwards joined as a partner in the firm and the firm has been appointed by the company which has not completed 10 consecutive years as on the commencement of the act even though the person has acted an auditor as a proprietor and partner of a firm for more than 10 years. In this circumstances whether the firm can continue even after 2017.