Hi Karu1,
They send a letter to my Centrelink account which confirming should have response from them before 6th September. Perhaps you should check yours Centrelink message (it doesn’t shows on Centrelink app but it will show on Computer.)
They will even text you to your mobile when they needed to call you to confirm your AOS after the due date “A Department of Human Services - Centrelink Service Officer will call you today from a private number. Please answer this call. Do not reply by SMS.” This is what they texted me, unfortunately, I missed the call (private number) as I was oversea and have rang them to ring me again. Hopefully will receive their call this week.
Note: If you missed the call, make sure you ring them 132 850 AOS support team. Or else you have to wait for a few more weeks for their call. And also check your Centrelink to ensure you allowed for email, text message, or phone calls or else they won’t be able to send you any confirming letter.
My friend applied 4 months earlier than me and her parent got the visa. She advised that after the phone call for AOS should be paying the first instalment in the next few weeks and she paid for second instalment a few days after the first instalment, after second instalment, the next day her parent visa was granted.
Hope this will help. Thanks.