Transport for NSW deputy secretary for safety Tara McCarthy said the penalty period would be enforced to account for additional road users surrounding the national day of mourning public holiday on Thursday.
"Although this is a sombre occasion, there are still likely to be more people out on the roads over the next few days and over the weekend with the school term ending on Friday, so it is important we all take extra care," McCarthy said.
"The last thing we want to see over this period is an increase in road trauma, which is why double demerits will be in place like they would for any other public holiday to deter people from doing the wrong thing and putting lives at risk."
Fordham said the hasty imposition of double demerits seemed to contradict the intention behind the public holiday, which is a day for paying respect to the Queen after her historical 70-year reign.
"I can understand it when you have a standard public holiday and you've got more people hitting the roads, but I'm not sure there are too many people who are going to be heading out and about on the National Day of mourning," he said.
"That's not the idea behind the whole thing."
Road transport regulation mandates double demerits over a long weekend when a public holiday falls on a Thursday, Friday, Monday or Tuesday.
Motorists who speed between 10 and 20km/h over the speed limit could see six points and $288, while the same offence in a school zone would result in eight points and $369.
Anyone caught speeding 45 km/h over the speed limit would be hit with 12 points of the total 13 points on their licence. They would also be fined an eye-watering $2547. The same offence in a school zone would cost $2704 and 14 demerit points - an instant loss of licence.
It seems doubtful that Queen Elizabeth II herself would have approved of the decision.
The independent monarch was known for driving herself around her Balmoral estate and even chauffeured visiting dignitaries.
On one such notable occasion in 1998, the Queen drove Saudi Arabia's Crown Prince Abdullah around the Scottish countryside when it was illegal for women to drive in his home country.