This has been talked about a lot. 1. You can’t apply for a DTV if you have a valid visa issued by the MoFA. It needs to be canceled first. 2. You must stay out of Thailand through the entire process of applying for a DTV. If you do scam the system and re-enter early (and they don’t figure that out), you need to exit and renter to switch to the DTV. You can’t switch to it while in county
Anonymous participant also, as a FYI, there are 4 consulates in the US and each has different requirements. Might want to ask for specific feedback for the consulate you will use.