Seeking an extension of the period allowed to stay in home country

I’m a student currently studying in Kerala, India.

I had returned from the UAE to Kerala on the 23rd of March 2021. According to the 180 days rule, my next reentry date is set to be on 19 September 2021.

But I’m not sure if I’ll be able to make it as I might have exams. Is it a must to enter right on that date or are there some days of extension?

Or anything else I can do?