Exemption from cs training 15 months

I will be clearing cs executive exam in December 2012 exam.assuming I can join training soon after result I.e from March 2013....meanwhile I got a job under a practicing company Secretary and I will be joining from 1st July and I might work for about 6 months before I can actually start with 15 months training.can I claim exemption Upto 6 months from compulsory 15 months training.....please help