Nobody can help it, we have to go with the flow. For limited number of students a change in exam dates could be opportunity to learn those topics or prepare better, but for majority, a change in date is really a put off.
However, if you are the one who is waiting for the fresh exam dates here are some suggestions in case if you fall in my category.
1. Dates are rescheduled keeping your safety in mind, maintain social distancing. If you cannot leave hostel maintain proper hygiene. Biology says, bacteria and viruses loves dirty environment. I am not sure in what percentage keeping your surroundings clean will help in fighting with COVID-19 virus, but if you maintain a clean atmosphere, for sure you will prevent from many other diseases. However, take precautions to keep yourself safe from n-corona virus on very priority.
2. Pursue an indoor hobby. Since how long you have not played with Guitar or not seen your favorite movie. Chill, relax and make your day while staying inside. Learn cooking or read some books. Learn one new thing everyday that require to stay indoor and you will realize you have learnt a lot while alone.
3. Solve some old question papers: I suppose you are well prepared to take the exams any dates, download some old question papers, or may be older, and take the test in exam like conditions.
4. Pursue writing: Who knows you could be next Sidney Sheldon. Or redesign your home using old things. Or learn a new computer language. Why not to learn some Python instead. if all this not help take to Rubik's Cube. Period!!!
5. Relax. Though such holidays are really unfortunate that too when its require to stay locked, but make maximum of it. Do you remember when last time you really rested well without worry to catch up with something early morning. Give your body and mind complete rest, getting bored is not bad either.
Stay inside; stay safe.
Help the world to fight with novel corona virus, your contributions will make significant impact.