Sample date (self-certified by you) and report date (when the results became available).
There are two times stamps on your Certificate — the first is the "Sample Date" which is the day and time you self-certify collecting your sample in (provided by you during your kit registration), and the second is the "Report Date" which is the date and time when your results became available.
The 72-hour requirement is dependant on what the airline advises — typically, they ask for the "Sample Date" to fall into the 72-hours.
If you have any further questions, please contact us via support@rightangled.co or alternatively please use our live chat service (Mondays to Fridays 9am-6pm)