Hello,

Usually IITs or any such institutes do not reschedule their interview date. As your semester exam and interview falls on same day, its very tough to accomodate both of them together.

Check the interview schedule. Sometimes, when you have got any exams to attend, they ask you about it on the interview day and take your interview first and allow you to go after your's is over. So you may try that.

Again confirmation from IIT Bombay is trust worthy.