Can I switch from a Non-O dependent visa to a Non-B work visa in Thailand without returning to India?

and just like that we're done. good luck to the O/P :)

I have not seen people on Non-O visa/extensions based on "trailing spouse" (being married to a foreigner who legally works here) be able to get OFF that and get a Non-B visa inside the country.

Now it might <- (read that as MAYBE) to cancel your current extension based on being a trailing spouse, get ON a 60 day covid extension and then apply for the Non-B from that but that's 100% going to come down to whether the employer can meet the requirements to apply for the 90 day Non-B visa at the immigration office. Remember the requirements inside the country at the immigration office are far more stringent than they are outside the country at a thai consulate.

Good Luck with it, you need to be talking to your employer and the immigration office you'll be dealing with.

Non-O trailing spouse to Non-B is quite difficult if it's possible. First, you may need to check your local immigration office if they allow.

That questions answer is between you and your employer and Thai Immigration ...it can be done inside Thailand but requires cooperation with all of those mentioned above.