From what I have seen. If you apply to embassy outside of Thailand they accept proof of funds in overseas account. It is only applications inside that stipulate the THAI BANK ACCOUNT.
I was in Phuket immigration on 25th and they were turning anyone applying for covid extension away. Saying they are not doing it any more. Only select cases are getting. I was given 2 months on TR visa but been similar time to you with alot of extensions. I was given 2 months as was just starting process to change to Non-O marriage visa.
1st number worked for me today. But you have to keep calling back. If they say you will get email in 15min and you don't keep calling. Finally approved 3 weeks later
Australian side need Certificate of non impedance CNI. This and a few other documents need to be translated to thai. Australian Embassy give you list of reccomended translators
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