Hi Nelly, my husband's friend applied at the end of August and got his 820 at the end of October, so it was just two months waiting for him. He lodged his application in Sydney. He got every document ready except Form 80, which I guess he later added. He did not go through 300 but he has been living in Australia for 3-4 years on other visas. And he's from China.
As for me, I'm from Malaysia and I applied for 820 in Sydney in early October. Mine is a decision-ready application as well. I did not go through 300. So far I have only received an email from the department acknowledging that my application is valid, together with the grant of Bridging Visa A, etc.
I'm not worried about anything, really. Soon after my BVA kicked in, I applied for a Tax File Number, and enrolled into Medicare. Currently I'm looking for a job. In terms of visa, there is nothing I can do now except waiting patiently for my 820 because you really don't know how long it will take. When things are beyond my control, I will just let it be.
Here's wishing all of us a smooth journey to 820/801.