Passengers holding non-refundable tickets will not receive any refund after the 24-hour risk-free period.
You will get a full refund with an upper class ticket regardless of whether it is a refundable and non-refundable ticket.
Azul Airlines cancellation policy says If you cancel your tickets 2-3 days or few hours before the scheduled departure, a penalty will be charged.
In case of flight cancellation due to unforeseen natural calamities or airline errors, passengers will receive a full refund or alternative flight on another day.