Or you could just search the RTA -
Speeding penalties
As taken from this link
What penalties apply for speeding in NSW?
If your vehicle is detected by a fixed speed camera, mobile speed camera or Police Officer and a penalty notice is issued, you will incur a fine and licence demerit points. P1 licence holders will have their licence suspended for at least 3 months for any speeding offence.
Here is the fine
More than 20 km/h but not more than 30 km/h, is 4 demerit points & $338 fine.
So not sure if you will lose your licence for this also as I think P licence holers only have 4 points?
So that could be 6 months if you get stung for both.
2 options here
1.suck it up and take the fine, points and loss of licence.
2.talk with a lawyer and see what your options are as you
may be able to dispute the fine and say you were doing 19k over and only get done for 3 months.
Nice to see someone admit they did the wrong thing too!