What should I put for the departure date on my Non-Immigrant B Visa application for teaching in Thailand?

Okay, let's get to the bottom of this Non-Immigrant Type B visas are sold at thai consulates two ways

A 90 day single entry Non-B that lets you enter the country ONCE, get stamped in for 90 days and then you apply for an extension inside the country at the immigration office in your area for a year extension based on employment

OR

A year-long, multi-entry Non-B that let's you enter the country as many times as you want during the year the visa is valid for and every entry will get you stamped in for 90 days. <- People on this visa do what's called "border bouncing"; they get a 90 day stamp when they enter, when it runs down they go to the border, stamp out of thailand, stamp in and out of another country and stamp back in to thailand to get a NEW 90 day entry stamp. IF they do that every 90 days for the validity of the visa they can get 15 months of stay out of a visa that is valid for a year

NOW it is totally up to the consulate you're applying at whether they will issue a Non-B as a 90 day single or a year long multiple entry for the job you are going to be employed for.

@Ster****

, I know people who teach here for government schools on year-long, multi-entry Non-B visas where they bounce every 90 days rather than get yearly extensions from the immigration office.

for a non b you will have to leave every 90 days .