Change non convertible preference shs to convertible pref. s

A Company XYZ Limited, issued Non-Convertible Preference Shares on rights basis. However, the company now wishes to change the terms of issue and change the preference shares to Convertible Preference shares and convert it to equity at a later date. 

First, is this possible under Companies Act, 2013? If Yes, under what provisions and what is the procedure?

Thanks.