Changing articleship firm after 1 year completing?

Respected sir,

                    Is there any possibility to change the articleship firm after completing 1 year in old firm. ?

Please suggest possibility of the same. If my old firm principal are ready to give me termination from his firm and 

also new principal accept me in his firm. ? Can is it possible after completing 1 year in old firm ? 

Please, suggest me on the above.