@Chantal *********
I applied through Canberra.
I moved savings from my home loan account (redraw) into a savings account I was happy to provide them with, but I moved like AU$30k (way more than required) and highlighted my weekly pay transactions on the statements, so they could see where the money was coming from (my employer)...
It wasn't a problem, but I I kept it all in 1 single account.
I agree with a previous comment too, keep it simple keeping your Thai account out of it.
Now, what I'm confused is what you mentioned about the income requirements... I'm not sure I understand what you mean about $250k in payslips plus $250k in savings...
As far as I know you have to show the $500k in an account (or multiple combined), but payslips don't come into play (happy to be corrected on this).. just make sure you apply through the right embassy, as depending on the state you live in, you have to go through Canberra or Sydney... (at least that's the guideline on it )