Hello, I'm staying and working here at Samui. I have a NON B Visa (Multiple entry) that will expire on November 8 2018, but my stamp will expire tomorrow (October 18, 2018). I changed my job and I need to change my Visa into Single Entry but the documents from my employer is not yet finished. I went to Immigration and they said that I needed to go out of Thailand by Plane and comeback so that I will acquire 3 months more of extension. Do I really need to go by plane not by bus?
TLDR : Answer Summary
The user is currently working in Samui with a NON B Visa that is about to expire. They were advised by Immigration to exit Thailand by plane and return to get a new 90-day extension. However, a commenter suggests that traveling by bus to a neighboring country and returning is also a valid option to renew the stay.