I never heard that. I gave 6 months statements they checked and then check my bank app in phone. You can try to be dodgy if you want but you will not get passed
it's easier to do the extension you just need correct paperwork. 1900 bht and about an hour out of your day. Next time he will know. I have checked with my immagration office already and have all prepared you can apply 45 days prior to the 180 days so plenty of time
You school needs to cancel your work permit. You them leave Thailand and your non b will be canceled also. The visa is tied to the work permit. You then apply for your DTV and there will be no problem. That's how l did it. DTV in Vientiane 3 days pick up new DTV and bus to udon Thani same day no questions asked from immagration at border. Stamp 180 days
Even with an agent the agent completed the paperwork but you give him all the documents and they send you outside of Thailand to apply. You pay accom and travel. It must be an embassy outside of Thailand. You may be called for an interview at that embassy. So you must attend. You just don't want to admit your wrong. Why don't you say who can do it inside Thailand let everyone know so they can go there and get dtv