Hold onto your pocketbook as you are privileged to get NBN services. Unless you were fortunate to get the FTTP with a landline option and battery, you will not have back to base service from FTTN, HFC, or any other alphabet type service. Options are to buy an IP capable panel that can easily be subverted by cutting the all so obvious NBN connection, or to go with a mobile back to base service that requires new hardware (depending on the vintage of your alarm, can be $400) to use mobile services, with monitoring costs going from roughly $35 p.m.+4 x 1300 call charges to $75 p.m. The better solutions have Telstra and Optus SIMs and report daily instead of weekly to help justify the cost increase. BOHICA!