Seriously though, this has become something accepted and completely normal. Congestion has become such a blanket term for the shortcomings of this server and I'm pretty sick of it. I'm trapped between having this speed from 6 pm to 10 pm or later or going with Optus option of leaving the contract (To which there are no other providers in my area). I really don't see why I should be paying full price for this.
Sorry for the delay getting back (Camping)
So no NBN for 6 more months (although FTTC should be very good - lucky you!)
Optus should be able to rectify those speeds but with the NBN so close in your area its likely they're doing/spending the bare minimum to keep the cable network running. Cable would be the fastest option unfortunately but if you keep getting speeds like those perhaps ask Optus to move you to a wireless solution (month to month only and preferably with a free modem/setup costs.). Vivid Wireless are Optus and offer 12/1 Mbps in your area. Optus also have something called 4G+ which may also be in your area and offers much faster speeds.
Otherwise you may need to just hunker down and wait for 6 months.
Apologies for the delay in getting back to you and your internet slow speeds @Jarrens. Did you raise this with Tech Support before and they advised you that the connection is affected by congestion? If that is the case then you are best to speak to our Retention team on 133937 - Mon - Wed: 8:00am - 7:00pm EST Thur - Fri: 8:00am - 8:00pm EST Sat: 9:00am - 6:00pm EST to look at your options as there is no quick fix for congestion, sorry. Kartik