Guess it depends on what is meant by notification...
If, as they say, it means the Telcos just have to write a letter outlining the changes, then it's not onerous.
But I suspect there is rather more to it than that; I suspect the AG dept would then seek further clarification from the telco (there is hardly likely to be enough detail in a "not onerous notification letter" for the AG dept to understand what the change means), and then they would be likely to seek to block or amend the proposed changes causing untold headaches for the Telcos.
There wouldn't seem to be much point to the law, if all the Telco had to do was notify that they were making a change that made it impossible to do wiretapping and that expempted them from their wiretapping obligations. So it's rather more likely that the AG dept would be seeking to have some oversight of the Telcos network design.
Of course Politicians and Buearocrats are well know for saying people are wrong without providing any further clarification of where exactly is wrong. This allows the pollies / buearocrats to later claim "no we didn't lie. you're twisting what we said (cause we didn't really say anything substantative at all) everyone just misunderstood what we said, but too bad the law is passed now so you just have to suck it nah nah na nah nah!!!"