Note that you will have to prove minimum income of 2800 USD for a 3 month period in the form of paid invoices from your freelancer clients as well as the 16k in the bank. If you register your own business you can also write the document required to prove you are allowed to work remotely, another criteria that needs to be met for the application.
I just completed my first 90 check in today at 8.30am. I am in Pattaya and visited Jomtien immigration office. I completed my TM47 at the office across from immigration and was second in line for the 90 day check in. They processed mine on the spot and was by far the easiest immigration process I have ever been through. You need copies of your passport, your real passport and TM30. Thats all
I called the Australian Embassy (Canberra) and spoke to them as a follow up to my urgently needed DTV as well. They were very polite and super helpful. I had the visa approved in the next 2 hours after expressing my urgent requirements, because like you I had flights and accommodation booked and did not want to lose money