14 October 2013
There is no prescribed time for the CA final reg. Your CA Final attempt doesn't depend on CA final registration, Your Final attempt depends on your Articleship reg. The last date for Articleship reg. to appear in CA final May,2016 is 31st Oct,2013..
You can register for CA final at least before filling CA final exams form, i.e at least 3 months before exams...
I want to clarify that there is no time gap is specified for final registration. You should have a valid final registration number at the time of filing of Final examination form with Institute.
As per Regulation 50 of the CA Regulations, 1988, a student will be eligible to appear in Final Exam, after completing of 30 months (2 Years and 6 months) of article ship.