Hello
Sorry but you can take only two attempts of the IISER Aptitude Test and that too in consecutive years. You can give it only in the year you passed your 12th board exams (1st attempt) and the year just after your 12th exams (2nd attempt). Hence you cannot write the test after two or more years of completion of your 12th boards.
Hope it helps
To check the eligible for IISER Aptitude test check the link given below
https://www.google.com/amp/s/engineering.careers360.com/articles/iiser-admission/amp
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