Hi Again,
Other members far more experienced than me have commented on other pages that Police can change errors on traffic type fines.
I'm still guessing it's usually going to be state / territory specific as it's mostly gonna be state law. So good idea to check your local laws and procedures for transport depts and police in your state.
Below is a link to a Queensland Police manual
https://www.police.qld.gov.au/corporatedocs/OperationalPolicies/Documents/TrafficManual/Chapter8.pdf
It's describes in Chapter 8.7 in detail about how infringements are to be cancelled / waived. So it is possible for Police in Qld to still do it. But how often it occurs and what type of error if fatal enough to lead to cancelling / waiving an infringement. Not sure - see manual notes. Sounds like final
decision rests with a more senior officer - eg could be someone like the district superintendent whom u write to - check your state procedure / rules to see if it's possible to request review of infringement error - NB this is very different to contesting in court (best avoided) - in Qld you would like write in / apply for review of ticket error ASAP - check on any fine / notice form too in case it states how to this.
Other states may well be different.