Some detail of atc of the c.a.

I AM A  C.S. I HAVE ALSO COMPLETED BOTH GROUPS OF IPCC AND 1 YEAR ARTICLESHIP UNDER A C.A. BUT NOW I DON'T WANT TO CONTINUE MY C.A. I JUST WANT TO LEAVE IT HERE.
 I WANT TO ENROLL FOR ATC. PLZ TELL ME IF I CAN CONVERT MY 1 YEAR ARTICLESHIP TO ATT (ATC TRAINING) OR THERE IS DIFFERENT KIND OF TRAINING TO UNDERGO ?