Read the post again. He thought the date was 20th April which would just be 40 days so he was asking if the quarantine had already been reduced to 10 days but in fact it’s a thai style 4 and the date on the stamp is 24th April 👍
Depends where you are from. The U.K. is result must be issued within 72 hours of the departure flight time from the U.K which means you could in effect have your test out of the 72 hour window 👍