Aicitss course

Hi Friends,

I converted from CA final old syllabus to new syllabus. I registered for articles before 2013 only and i completed articles and ITT course at that time. Now i applied for NOV 2018 exam. I got a mail from ICAI that it is necessary to complete AICITSS course before appearing for exams. I have not completed GMCS course earlier. I previously attended exams in old syllabus. Is it necessary to do AICITSS course before going for exams or can i do it later.....Pls suggest me......