Look... He mentioned he currently holds non-b visa which can be transferred without flying out following BOI benefits. I've done the case before last month and it was successful. But his expiry date is 17 March so l just offered him another option.

In order to submit non-b visa. All employees need to have this kind of visa (if they cannot do domestic transfer) to be origin to apply yearly visa. That's from my experience from dealing with BOI and Chaeng Watthana 6 years.

Here's an example.

You can do domestic visa transfer without flying out. You have to discuss with HR or whoever work on visa whether there is position to be ready to register your profile with BOI system. If not I'm afraid the time is quite tough to do profile registration. So what I advise is to get the void stamp before visa expiry date. Flying out to apply temporary non-B visa from Thai consulate located overseas. Finally do profile register in order to obtain or 4 years visa (depending on type of business and agreement with BOI)

Prohibited under the unsufficient fund reason.

No, but It was written as not sufficient fund.