this might not be the right answer but I think i heard this once on here before. wherever you are you need to go to a thai embassy in that country and have them flip it to your new passport number. The embassies always have thai immigrations people in there.
You're not stateless anymore you are a citizen of America. I recommend contacting an immigrations lawyer here in thailand. They deal with cases in this field all the time and would be able to give you the best path if one is possible at all. I recommend integrity legal in bangkok. he has a YouTube channel you can search him there. He's an American lawyer that manages a team of thai lawyers that specifically deal with thai and U.S. immigrations.
It depends on the embassy you're applying at. Some even want 6 months. I also applied while in thailand. Which is a lot harder then doing it in your home country or another country you are staying at for a while. I have an agent i used that did all the work for me and ensured it went smoothly. They also paid for the hotels while I was in Malaysia and the visa was processing. The line ID is Successvisa789 ask for bee.
Line ID Successvisa789. Agent bee helped me out with my DTV visa. She was very professional. I would recommend her to family and friends. We even had a few issues and she was able to over come them in just a few days. They talk directly with the immigrations office to ensure quick and easy processing. I also needed some paperwork from her to unfreeze my bank account about 6 months after my visa was completed. She was able to get me the paperwork I needed to unlock my account in 2 days. 10 out of 10 for service, knowledge of the process, processing, and customer care.
I watched integrity legal the other day and he said even on the privileged visa people were having problems. I also read on here about a guy having problems with opening an account on the LTR visa. He was saying banks didn't even know what that visa was. In general getting a bank account seems to be a nightmare. I was lucky I got an account on a visitors visa before I even got my DTV last year. My account was frozen then when I showed all my paperwork for my DTV visa they unlocked my account. This is definitely something that's difficult to navigate at this time.
You will be lucky if you can find an agent that knows a branch that will accept the DTV. If you own a condo, you're married to a thai on the DTV you can for sure.