i assume you are not familiar with the requirements as laid out by the thai consulate in New York. I was told by the consulate that it was from time of issuance of result. I had to make a stop in Los Angeles CA in order to be tested and safely inside the time constraints in case of flight delays or cancelation. I most certainly would not have extended my trip with a 2 day stop in LAX if I had not been instructed that it would be the prudent thing to do to negate the flight/layover time in my itinerary. I am only expressing my experience. As I said more than once, I don't give a fuck what anybody else chooses to do. Check with the consulate in your local are and country, the opinions of the people in this forum don't have any value (yours or mine) call the fucking consulate and get the answer from the source.
Just do it your way, I will not post a form that could be easily copied and altered to be used fraudulently. Look, you just go ahead and do it your way. I spend 3-4 months here every year (for the past 15 years) Trust me on this, all you need is one immigration officer who is having a bad day to look over your docs and your ass will be on a plane back to the UK. But by all means, do it your way, I am only posting my experience and opinion. I truly wish you the best of luck. Taking chances is the spice of life right ? Go for it.
So you have not entered the Kingdom yet ? I wish you the best of luck. Feel free to do it your way. And here is a quote regarding the type of test required: ou need to obtain a COVID-19 lab test result indicating that COVID-19 is not detected. The COVID test must be by RT-PCR method (the method must be clearly indicated on the form).