When I used this office to get my Non OA a few years ago it was packed with people and agents getting visas. It was walk in service at that time. Most of the people were Taiwanese getting tourist visas.
Once you get stamped for 1 year of Admitted to Stay until July 2020 you can go to immigration and get a single or multi re-entry permit. This will allow you to leave Thailand and still keep your same admitted to Stay.
Two extensions ago at CM I used two accounts with a single letter from the bank. The IO said that I should have had two letters and that the money should be in one account. The extension was granted. I use a Fixed account for the 800k.
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