Carry on is a significant source of revenue for JQ. Sometimes you are lucky other times they are mercilous with weighing everyone’s carry on, and each and every item. If you are over 7kg you are sent off to the person with the EFTPOS machine who will sell you either +3kg of carryon allowance or check it in the hold for around $60 if you are over 10kg. If you have purchased baggage and did not use it, and are over on carryon at the gate they will not allow you to use that allowance or turn a blind eye. (There is mention of this in the T&Cs online). Revenue is revenue.

Ie you cannot chance it and say let’s give it a go and worst is that they check it. You will pay an large fee.

KF