https://www.devex.com/people/does-singapore-air-have-a-24-hour-cancellation-policy-new-rules-1970428 https://www.devex.com/people/can-you-change-dates-on-turkish-airlines-policy-rules-1970426 https://www.devex.com/people/does-singapore-airlines-have-a-24-hour-cancellation-policy-full-policy-new-1970437 https://central.xero.com/s/question/0D58V00009OR4NYSA1/can-i-cancel-my-allegiant-flight-without-a-penalty