March 2020, I figured this would be a great topic as many events have been canceled for the next few months. Current cancelations have affected many (Dj's, clients, venues, and many more.), but I'll speak on the perspective of Dj's and clients.
A contract is put into place for the protection of both parties. Aside from the current crisis taking place, these terms and conditions layout important information regarding deposits, cancelation, postponement, insurance, etc. I'm not saying your Dj should have a contract, but if they don't, you may want to ask questions regarding these possibilities.
Deposits may be lost if the event is canceled, but applied if rescheduled within a certain timeframe. Dj's might not be available if postponed, but they could assist in finding coverage for the new date. These details might not seem important, but situations and emergencies do arise, as the current pandemic has displayed.
I hope this information is helpful and finds everyone at home practicing safe habits.