I got my Thailand Pass! Four days later (today), Thai Smile cancelled my flight.
I emailed AQ.in.th, the company I paid to help with my Thailand Pass (they were great, getting done in 5 hours what I couldn't do myself in 3 weeks), and they said "It's okay if you change your flight and it's on the same day, because you can use that Thai Pass QR code within 72 hours of the stated date."
Is that true, to your knowledge? Can that Thailand Pass be used for a different flight on the same day without getting a brand new Thailand Pass?
Thank you for the guidance!
TLDR : Answer Summary
The Thailand Pass QR code can be used for a different flight on the same day as long as it falls within a 72-hour arrival window from the original scheduled time. It is advisable to inform your hotel about the change, especially if your new arrival time differs significantly.