Also when you've got a new visa. I haven't changed the address but came back from overseas with new O-A visa. Phuket immigration insisted on new TM30 before 90 day reporting.
For issuing a O-A you can use a foreign insurance during the 1st year and you should be stamped in accordingly . In that case it should have been 89 days ... 🧐
But that, at least, makes some sense to me. It means they accept the O-A visa with international insurance for a total of the 1st year (or the length of the insurance accordingly )
Have you checked the SYD embassy webpage . I checked my German embassy webpage and found that i still could have the 1 year NON O (over 50 years old ) multiple entry for 1 year without that insurance story but have to leave every 90 days .