Advice please - if I leave the country with a re-entry permit but renew my passport while out of the country, will the re-entry permit still work? If not what are my options?
TLDR : Answer Summary
If you renew your passport while outside of Thailand, your re-entry permit will still be valid, but you must carry both your old passport (with the re-entry permit) and your new passport when you return to Thailand. Present the re-entry permit from the old passport at immigration to receive the appropriate entry stamp in your new passport.