Jomtien standard accepts your extension application when you have 30 days or less with your stamp, but will accept it earlier if you provide a reason on your side.
, unfortunately, no one other than your embassy can notarise your income for your immigration/visa purpose. You need to get your visa outside Thailand to enter on it.
, You are talking about the step when you change the method from the banked money method of 800k baht in a Thai bank account TO a monthly deposit method, not the opposite way (what the OP want to do)
Why not visit your local immigration office to discuss your schedule, bringing your detailed itinerary and confirmed air tickets? In advance or just before you submit applications.
If they can accept, they may complete before your departure. Or they may be able to make the under-consideration period longer.
Even if they say no, nothing is going to be worse than the current situation by asking them.
, many embassies/consulates don't specify the country where your bank is located. Usually, you can use a bank account in any country as long as you can provide the necessary documents at that embassy.
, there is no specific timeline for it, as long as the main applicant is on the correct visa/extension. BUT I don't think there is an embassy/consulate that would issue a Non-O visa for a dependent of a Non-O retirement holder.
You seem to be mixing some information. What you are referring to is the conditions for applying for a 1-year extension after obtaining an in-country visa for a 90-day initial stamp.
For an initial in-country visa application, there is no condition about maximum remaining days with your current stamp, while there is one about minimum remaining days, 15 days or 21 days, depending on the local immigration office.
You can apply for an in-country visa even on the next day you arrive, as long as you meet the requirements.
As a rule, monthly income method for a 1-year extension based on marriage to a Thai national is one of:
1. Embassy letter/affidavit for monthly income
2. Monthly income based on working legally in Thailand.
Monthly international transfers is not one of the measures that are stated.
Some offices accept monthly international transfers of minimum 40K baht every month with proof of source of funds. But as it is not the stated method, immigration office can say no.
You should talk with your local immigration office for details and whether they would accept it for your specific case.
You may need to cancel the extension based on employment to apply for an extension based on marriage to a Thai, regardless of whether you get a new Non-O or not. In that case, you need to cancel the extension officially by using the letter from your ex-employer at the immigration office that issued the extension, it'd be the Chaengwattana office in your case, no other office.
Just leaving Thailand and coming back is not enough for this.
, KL is known for a rather long processing time. You need to check with them. I think I saw the post about that Non-immigrant visa processing time in KL is a bit shorter than DTV/tourist visa, but I cannot assure.