We found the portal easy to use for rapid and PCR test results. We did not have antibody test results and I am unsure if they are treated differently. For PCR and rapid tests you must get tested and get the results within the 5 day window immediately prior to your arrival. Submission was easy to do and acceptance responses were received back from the portal in less than 24 hours. We brought printed acceptance reports and test results with us on flight to present as backup for the arrival screening at STT.