Back in October, we seemed to be making progress. Our Deputy Mayor had met with a Telstra representative and they agreed to "community remediation", which is a term I don't understand - but is sounded good.
The Telstra rep has since moved on, and the problem has been passed to someone else at Telstra. I rang that someone else today, and had a good chat with them about the issue. I've emailed them the history of this case, since there was no handover, and I guess the whole process will start from scratch again.
At least the problem now belongs to someone at Telstra. It is no longer somebody else's problem.