Hello Aspirant,

All the IITs will run preparatory courses of one year duration for SC, ST and PwD candidates which would  to prepare them to pursue the academic program to which they have been allocated. At the end of this course, candidates are declared as pass or fail.

After successfully completing the course, you will be allocated your branch.

But, at the end of the course, if you want to give JEE Advanced examination again you can give it owing to its eligibility criteria.

Also, it is not possible to get admission into any IIT directly into a B Tech course if you have a preparatory rank.

Hope that helps. Good luck