As far as I know this is not approved/published, and still going through the government processes. and no definite starting date. many ideas are discussed, some get approved, some gets debated forever, some approved.
could just go to Thailand 60 days visa exempt, then find a local agent, does cost a bit, but quite easy and painless. They'll also get you setup with a bank account.
you can't book your return ticket based on a "possible" extension. it has to be within the initial 60 days "assuming visa exempt". Is best to get a ticket that has cancel/rebook. If you don't probably not going to be immigration, but your airlines will not even give you a boarding pass, if you do not follow the rules.
ask 10 boarder agents, and you'll get at least 10 different answers. There's no legal limit, entirely up to the boarder agent standing in front of you.... hope he's not just had a fight with his wife or boss "or both". post is just more fake news
If you enable "WIFI Calling" you can get your SMS 2 factor codes for free, when connected to a local WIFI "like at your condo". Some companies automatically enroll you in their high priced international plan, as soon as your phone gives the phone company notification you are not in USA. however most also you can opt of that in advance. Verizon used to have to OPT in, but now they figured out they make more money by auto opt in, and you have to call them to opt out. Not 100 percent sure if 2 factor works with google fi, never tried, but many companies enable something called KYC and if so, it might not work for you.
If you make smaller transfers, should be instant. There is a FAQ on the website that gives you to limit for instant, vs waiting. Then just make several instants vs one big one per month.
all the requirements were already met from your DTV "the person getting the original DTV". dependent visa is pretty much what it says. however as each embassy makes up their own rules/requirements, nobody but whatever embassy you are going to apply to could possibly give you the exact answer. I've not seen anywhere a difference for "single person" vs, "married", so not sure where you got that from.