Articleship completion due - principal not available

Hello All,

I am under Articleship Training in a CA partnership firm and the training completion is due on 2nd Sept 2016. The partner under whom I was initially registered has gone out of country for around 2 months or more. My query is that since he is my official principal so do I have to wait for him to come back to India and to get my Articleship completion Form 108 signed by my pricipal only or I can get my form signed by any other partner of the firm. Please help me with this problem so that I can submit my signed completion form 108 to the ICAI in time without any delay and to have a hastle free completion of my training. 

Thank You
Siddharth Singh