My experience entering with a new passport
I had my DTV back on April 2025, I enter Thailand for 2 weeks every 2 months on my DTV.
This time i had my passport renewed and I entered through BKK airport, I had my old and new passport + DTV visa printed
Immigration officer took old passport copied something on the computer then stamped the new one.
Asked what to do next time, she said only carry my new passport and DTV visa next time no need to bring the old one except for first entry.
No question asked
Just wanted to share my experience