The government changes rules all the time. So just keep that in mind. I'm not even looking into the DTV in too much detail right now, because I won't need it until next June, and everything could be different by then.
I was able to get a Covid extension when my STV ended at the immigration office in Chiang Mai. Currently on my second Covid extension. I’ve been given mixed messages as to whether you can convert to any other visa type once on a Covid extension.