we have penalty for this in our salary already

our base salary is $35611
thats around $3500 pa approximately
it could work in both our favours to switch to DHP
I wasn't aware of any other penalty being included in our base, apart from the Daily Travel Allowance (DTA)
The Duty Hour Penaly (DHP) is another payment for working unsociable hours, weekends etc. So you would receive this depending on the times of your duties, i.e earlies, lates, BOC etc...