The part of section 31 of the Family Violence Protection Act 2008 that talks about the maximum length of time a police-issued notice remains in force now reads,
(3) The first mention date for the application must be—
(a) within 120 hours after the family violence safety notice or form of notice completed under section 27(3) is served; or
(b) if it is not possible for the first mention date to be within 120 hours because a public holiday means the first date on which the court will sit is more than 120 hours after the service of the notice, the first working day after the public holiday.
(This is also an example of how careful you have to be with AustLII. It hasn't been updated yet, and may not be for a while.)
Why 5 days instead of 3? I've no idea.
The provisions that create new offences don't appear to have come in yet.