For most of the sites if they received reliable information about the game they wouldn't be hesitant to do refund within 24hrs while some other sites would definitely take 48-72hrs while they put their eyes and ears down to source for information concerning the tournament before finally refund their bets. At some point it would be marked as void within that period but after thoroughly vetted they will lift it.
For voided bets, I think that the player must have to open a ticket. I don't know if this happens automatically. It happens automatically, and the option was bitcoin or any other cryptocurrency, the payment is will not be more than a few hours to twenty four hours. It the player has to open a ticket first and their option is like bank transfer or some other methods other than crypto, it will take a couple of days for refunds to be me. The criteria are the casino operation, the payment option.
It works automatically to my knowledge because if the bet is not valid the casino has to quickly refund it without any delay, and before a bet must be refunded as I said there should be thorough investigation, to know if the bet wouldn't resumed within next 2-3 days. But if there are concrete and valid information regarding the match then fine, they refunds within 24hrs+ be it cryptocurrency, bitcoin or fiat you will received a refund. I could remembered then, there was a game a booked and about 2 bet was voided and they refunded immediately the other game ended, they paid for only that winning and the rest was refunded, that is the total odds was 5, and the voided 2 match was 3.9 odds, and remaining was around 1.1 odd. Which I won and they refunds me.
Though this differs from casinos, I don't know about cryptocurrency casinos if they do refunds automatically like local casinos.