CIA actually helps you in presenting your finding during internal audit in more user friendly manner (if you have completed your articles and learn how to make an observation),
else, it helps you getting job for IA dept, or impress your susral etc 
I am an old player of this field, 10th BAC (1997), 12 yrs old, and have seen all done all status, worked in a large group as AM internal audit 2 year back
I suggest you better go for it and try to complete it in one attempt, further develop your auditing skills more sharp,
and why the hell you left the firm without having a job in hand, go back anf join the same firm till you finds a job !Thanx