Assuming you have a decent JEE Mains score, and about 75% in +2 you would be standing an even better chance of getting the branches of your desire(More seats are allotted for this stream). Since you have not provided your JEE Mains score, I will assume that you have not scored that well.

You must have known this by now, SASTRA has admission intake for UG courses in 3 primary categories.

1. Stream 1 (JEE Mains score(25%)+12th Grade score(75%)) - 70% seats
2. Stream 2 (12th Grade score) - 30% seats

Apart from this there is another category,

3. NRI Category (12th Grade score)

You can apply for the NRI category even if you aren’t one. Many of the students here in SASTRA were not actually NRIs but have got their admission in this category. I guess you just need to have a blood relative of yours as an NRI. The fee structure for them, however, is pretty much double the fee of the first two categories’.

If you really want to join SASTRA, then you could even join for the best branch provided to you at the time of counselling and study well in the first 2 semesters and slide to the branch of your choice. You need to keep your CGPAs as high as possible for this(I would recommend an 8.5+ CGPA). It’s a merit based (and vacancy based) sliding.

Conclusion: There’s a high probability. Just keep an open mind regarding the branch though. Best wishes!