Well that's what I thought too, I had a Non-OA with multiple entry and arrived at Suvarnabuma on the 22.Nov.. Immigration asked for the Health Insurance certificate. My Insurance, which I have for many years, starts September and is renewable every year. The Officer stamp in my Passport shows my stay until September 2026 and not for 12 months, as my visa from the Embassy stated. Also, there was no re-entry stamp. So much for the Non OA visa !!!!