Interview experience

I'm a recent computer science graduate actively seeking internship opportunities in Product Management. I applied for a position at a fintech startup in Bangalore. After successfully passing the HR interview, they presented me with a case study involving an International Airline. My task was to propose and implement features to address the issue, which I complemented with UX designs. I advanced to the next interview round scheduled for last week, but no panel members joined the meeting despite waiting for 20 minutes. I contacted the HR, and they informed me that the panel was occupied and would reschedule. They rescheduled the interview for today at 4 PM, but at 3:50 PM, I received a call from the HR, notifying me that the panel was currently busy and rescheduling it to 6:30 PM. Just now, I received another call stating that the interview will be postponed to 12 PM tomorrow. This is only the initial round, with three more to follow. I'm curious, is it typical for companies to follow such lengthy and multi-round processes when hiring interns?