I have checked your NBN-HFC service on our systems and all tests are passing.
A 12/1 plan with heavy household usage can appear slow at times because the 1meg upload speed becomes a bottleneck.
For heavy usages, a 50/20 plan will provide much more reliable speeds to heavy usage situations.
Here is a doc to help TS speed issues.
How would you define "heavy use"?
It is now not just limited to the afternoon dropouts, it is happening all day.
And i'm not talking about slow internet, i'm talking about NO internet. Dropped out, cannot connect. Computer restarts, modem restarts, multiple times per day. It's inefficient and it's unacceptable.
UPLOAD speed on base plans becomes a bottleneck when even a small amount of users are using the service. 1meg uploads slows everything down as everyone SENDS page requests, gaming, streaming requests.
Im not saying this is your issue, but thats why in this digital age of heavy usage, a 12/1 plan can grind slow very quickly.
I will re check your service.