For info - travelled on 90 day Non o visa issued by London Thai embassy - LHR to BKK via Eva Air 12/10/24 my ticket had return date of 24/3/25 (163 days)
In LHR Eva didn't ask to see visa, boarded with no issues. In BKK passport stamped with 90 day and no questions asked about 163 day return date. (Was ready to explain I was applying for Marriage Visa in Dec for 12 month)
Just my experience.