Articleship re-registration

Hello Sir, 

     I have taken transfer on medical grounds, and got the conformation from icai also. can u please tell me whether is it a restriction that we should join other C A firm which is 50kms away from my previous Principle's office as this is my third year of articleship training. please suggest me whether i should join another firm which is within 50kms or it should be 50kms away......please reply as soon as possible