As long as the delay to your flight does not compromise the required testing window for your destination, your certificate should still be valid. For example, flying to Singapore requires a negative certificate within 72 hours of your departure, but if your flight is delayed by half a day, your certificate may still be valid.
Regulations and restrictions are changing rapidly, so please check your destination government website for the latest up-to-date requirements. It is the sole responsibility of passengers to clarify in good time the testing requirements needed for their destination.
IATA Travel Centre:
Hong Kong Government Travel Health Service:
Outbound Travel Alerts:
Department of Foreign Affairs Travel Advice:
Ministry of Foreign Affairs Travel Advisory:
Singapore Government Travel Advice:
UK Government Foreign Travel Advice: