if where youre staying asks for a copy of your passport, or asks for a photo of the page, they are most likely doing your tm.30. every hotel i stayed in and even some "selfcheck in" accommodation asked, and sent me a confirmation of tm.30 lodgement. some have not. so it seemed to be the difference.
im a tax resident too at the moment in Australia, but if i move to thailand full time(or more than 6months a year), i am not returning to Australia to live (only to visit), thus i will have established social and economic ties with thailand, the test comes up with foreign resident for this.
interesting, do you stay in australia for more than 6 months? then you are a tax resident. Do you have social or economic ties to another country? this includes moving overseas and opening a bank account and setting up financially in Thailand too