Have you asked your school? Some can convert inside Thailand, and some cannot. For those that can, it can take more than a month between them having to apply to the Ministry of Education for approval, and then you must have between 14-21 days left on your existing stamp at the time that you apply for the ED Visa at immigration. If you don't have plenty of time left available to you, you might have to leave regardless.

@Lesia *********

flight numbers are the same every day. Every booking website like Google flights, Skyscanner, airline websites etc will show you the flight numbers

Go to a booking website. Find a flight you like. Print out the itinerary and upload it. If they want to see a real ticket they will then send you a request for additional information. Most embassies don't require an actual booking for a visa application.

I'm not sure what you are asking. There is no such thing as extensions when it comes to the embassy. Extensions are done in Thailand at an immigration office. The embassy only deals with visas.

The 90 day non-O visa does not have an insurance requirement.

The 1 year non-OA visa (a completely different visa) does require insurance, as well as health check, background check and other requirements.

@Lesia *********

No. They want to see your flight from where you are applying to Thailand.

Your embassy knows. Check their website

You put the arrival flight for Thailand. The last segment that actually lands in Thailand.

For departure, leave it blank, it's not required. But if you accidentally touch any of the fields, it will all become mandatory to fill out.

@John ***************

Which immigration officer? The one at your local office that you would be doing the extension with?

@Wayne ********

highly recommend LTR if you qualify.

@Wayne ********

Are you actually planning on going for the 2nd 5 year? I read a report from someone who went to immigration with everything that should be required, including the 3 million in a Thai bank account, and they were flat out refused by immigration and told it's not possible.

I believe Tod Daniels said most people abandon the 2nd 5 years and go and get a new non-OX visa.